SQLite Interface

Log analysis in lnav can be done using the SQLite interface. Log messages can be accessed via virtual tables that are created for each file format. The tables have the same name as the log format and each message is its own row in the table. For example, given the following log message from an Apache access log:

127.0.0.1 - frank [10/Oct/2000:13:55:36 -0700] "GET /apache_pb.gif HTTP/1.0" 200 2326

These columns would be available for its row in the access_log table:

log_line

log_part

log_time

log_idle_msecs

log_level

log_mark

log_comment

log_tags

log_filters

c_ip

cs_method

cs_referer

cs_uri_query

cs_uri_stem

cs_user_agent

cs_username

cs_version

sc_bytes

sc_status

0

<NULL>

2000-10-10 13:55:36.000

0

info

1

<NULL>

<NULL>

<NULL>

127.0.0.1

GET

<NULL>

<NULL>

/apache_pb.gif

<NULL>

frank

HTTP/1.0

2326

200

Note

Some columns are hidden by default to reduce the amount of noise in results, but they can still be accessed when explicitly used. The hidden columns are: log_path, log_text, log_body, and log_raw_text.

You can activate the SQL prompt by pressing the ; key. At the prompt, you can start typing in the desired SQL statement and/or double-tap TAB to activate auto-completion. A help window will appear above the prompt to guide you in the usage of SQL keywords and functions.

_images/sql-help.png

Screenshot of the online help for the SQL prompt.

_images/group_concat-help.png

Screenshot of the online help for the group_concat() function.

A simple query to perform on an Apache access log might be to get the average and maximum number of bytes returned by the server, grouped by IP address:

;SELECT c_ip, avg(sc_bytes), max(sc_bytes) FROM access_log GROUP BY c_ip

Note

For reference, the PRQL query would look like this:

from access_log | stats.by c_ip {average sc_bytes, max sc_bytes}

After pressing Enter, SQLite will execute the query using lnav’s virtual table implementation to extract the data directly from the log files. Once the query has finished, the main window will switch to the DB view to show the results. Press q to return to the log view and press v to return to the log view. If the SQL results contain a log_line column, you can press to Shift + V to switch between the DB view and the log

_images/query-results.png

Screenshot of the SQL results view.

The DB view has the following display features:

  • Column headers stick to the top of the view when scrolling.

  • A stacked bar chart of the numeric column values is displayed underneath the rows. Pressing TAB will cycle through displaying no columns, each individual column, or all columns.

  • JSON columns in the top row can be pretty-printed by pressing p. The display will show the value and JSON-Pointer path that can be passed to the jget function.

PRQL Support (v0.12.1+)

PRQL is an alternative database query language that compiles to SQLite. You can enter PRQL in the database query prompt and lnav will switch accordingly. A major advantage of using PRQL is that lnav can show previews of the results of the pipeline stages and provide better tab completion options.

A PRQL query starts with the from keyword that specifies the table to use as a data source. The next stage of a pipeline is started by entering a pipe symbol (|) followed by a PRQL transform. As you build the query in the prompt, lnav will display any relevant help and preview for the current and previous stages of the pipeline.

The following is a screenshot of lnav viewing a web access log with a query in progress:

_images/lnav-prql-preview.png

Screenshot of a PRQL query in progress

The top half of the window is the usual log message view. Below that is the online help panel showing the documentation for the stats.count_by PRQL function. lnav will show the help for what is currently under the cursor. The next panel shows the preview data for the pipeline stage that precedes the stage where the cursor is. In this case, the results of from access_log, which is the contents of the access log table. The second preview window shows the result of the pipeline stage where the cursor is located.

Log Tables

Each log format has its own database table that can be used to access log messages that match that format. The table name is the same as the format name, for example, the syslog_log format will have a table that is also named syslog_log. There is also an all_logs table that provides access to all messages from all formats.

Note

Only the displayed log messages are reflected in the SQLite interface. Any log messages that have been filtered out are not accessible.

The columns in the log tables are made up of several builtins along with the values captured by the log format specification. Use the .schema command in the SQL prompt to examine a dump of the current database schema.

The following columns are builtin and included in a SELECT *:

log_line:

The line number for the message in the log view.

log_part:

The partition the message is in. This column can be changed by an UPDATE or the :parition-name command.

log_time:

The adjusted timestamp for the log message. This time can differ from the log message’s time stamp if it arrived out-of-order and the log format expects log files to be time-ordered.

log_actual_time:

The log messages original timestamp in the file.

log_idle_msecs:

The difference in time between this messages and the previous. The unit of time is milliseconds.

log_level:

The log message level.

log_mark:

True if the log message was marked by the user.

log_comment:

The comment for the message. This column can be changed by an UPDATE or the :comment command.

log_tags:

A JSON list of tags for the message. This column can be changed by an UPDATE or the :tag command.

log_annotations:

A JSON object of annotations for this message. This column is populated by the :annotate command.

log_filters:

A JSON list of filter IDs that matched this message

The following columns are builtin and are hidden, so they will not be included in a SELECT *:

log_time_msecs:

The adjusted timestamp for the log message as the number of milliseconds from the epoch. This column can be more efficient to use for time-related operations, like timeslice().

log_path:

The path to the log file this message is from.

log_text:

The full text of the log message.

log_body:

The body of the log message.

log_raw_text:

The raw text of this message from the log file. In this case of JSON and CSV logs, this will be the exact line of JSON-Line and CSV text from the file.

Extensions

To make it easier to analyze log data from within lnav, there are several built-in extensions that provide extra functions and collators beyond those provided by SQLite. The majority of the functions are from the extensions-functions.c file available from the sqlite.org web site.

Tip

You can include a SQLite database file on the command-line and use lnav’s interface to perform queries. The database will be attached with a name based on the database file name.

Commands

A SQL command is an internal macro implemented by lnav.

  • .schema - Open the schema view. This view contains a dump of the schema for the internal tables and any tables in attached databases.

  • .msgformats - Executes a canned query that groups and counts log messages by the format of their message bodies. This command can be useful for quickly finding out the types of messages that are most common in a log file.

Variables

The following variables are available in SQL statements:

  • $LINES - The number of lines in the terminal window.

  • $COLS - The number of columns in the terminal window.

Environment

Environment variables can be accessed in queries using the usual syntax of $VAR_NAME. For example, to read the value of the “USER” variable, you can write:

;SELECT $USER

Collators

  • naturalcase - Compare strings “naturally” so that number values in the string are compared based on their numeric value and not their character values. For example, “foo10” would be considered greater than “foo2”.

  • naturalnocase - The same as naturalcase, but case-insensitive.

  • ipaddress - Compare IPv4/IPv6 addresses.

Reference

The following is a reference of the SQL syntax and functions that are available:

expr [NOT] BETWEEN low AND hi

Test if an expression is between two values.

Parameters
  • low* — The low point

  • hi* — The high point

Examples

To check if 3 is between 5 and 10:

;SELECT 3 BETWEEN 5 AND 10
0

To check if 10 is between 5 and 10:

;SELECT 10 BETWEEN 5 AND 10
1

ATTACH DATABASE filename AS schema-name

Attach a database file to the current connection.

Parameters
  • filename* — The path to the database file.

  • schema-name* — The prefix for tables in this database.

Examples

To attach the database file ‘/tmp/customers.db’ with the name customers:

;ATTACH DATABASE '/tmp/customers.db' AS customers

CREATE [TEMP] VIEW [IF NOT EXISTS] [schema-name.] view-name AS select-stmt

Assign a name to a SELECT statement

Parameters
  • IF NOT EXISTS — Do not create the view if it already exists

  • schema-name. — The database to create the view in

  • view-name* — The name of the view

  • select-stmt* — The SELECT statement the view represents


CREATE [TEMP] TABLE [IF NOT EXISTS] [schema-name.] table-name AS select-stmt

Create a table


WITH RECURSIVE cte-table-name AS select-stmt

Create a temporary view that exists only for the duration of a SQL statement.

Parameters
  • cte-table-name* — The name for the temporary table.

  • select-stmt* — The SELECT statement used to populate the temporary table.


CAST(expr AS type-name)

Convert the value of the given expression to a different storage class specified by type-name.

Parameters
  • expr* — The value to convert.

  • type-name* — The name of the type to convert to.

Examples

To cast the value 1.23 as an integer:

;SELECT CAST(1.23 AS INTEGER)
1

CASE [base-expr] WHEN cmp-expr ELSE [else-expr] END

Evaluate a series of expressions in order until one evaluates to true and then return it’s result. Similar to an IF-THEN-ELSE construct in other languages.

Parameters
  • base-expr — The base expression that is used for comparison in the branches

  • cmp-expr — The expression to test if this branch should be taken

    • then-expr* — The result for this branch.

  • else-expr — The result of this CASE if no branches matched.

Examples

To evaluate the number one and return the string ‘one’:

;SELECT CASE 1 WHEN 0 THEN 'zero' WHEN 1 THEN 'one' END
one

expr COLLATE collation-name

Assign a collating sequence to the expression.

Parameters
  • collation-name* — The name of the collator.

Examples

To change the collation method for string comparisons:

;SELECT ('a2' < 'a10'), ('a2' < 'a10' COLLATE naturalnocase)
('a2' < 'a10') ('a2' <nocase)
             0               1

DETACH DATABASE schema-name

Detach a database from the current connection.

Parameters
  • schema-name* — The prefix for tables in this database.

Examples

To detach the database named ‘customers’:

;DETACH DATABASE customers
 error: SQL statement failed
 reason: no such database: customers
 --> command:1

DELETE FROM table-name WHERE [cond]

Delete rows from a table

Parameters
  • table-name* — The name of the table

  • cond — The conditions used to delete the rows.


DROP INDEX [IF EXISTS] [schema-name.] index-name

Drop an index


DROP TABLE [IF EXISTS] [schema-name.] table-name

Drop a table


DROP VIEW [IF EXISTS] [schema-name.] view-name

Drop a view


DROP TRIGGER [IF EXISTS] [schema-name.] trigger-name

Drop a trigger


expr [NOT] GLOB pattern

Match an expression against a glob pattern.

Parameters
  • pattern* — The glob pattern to match against.

Examples

To check if a value matches the pattern ‘*.log’:

;SELECT 'foobar.log' GLOB '*.log'
1

expr [NOT] LIKE pattern

Match an expression against a text pattern.

Parameters
  • pattern* — The pattern to match against.

Examples

To check if a value matches the pattern ‘Hello, %!’:

;SELECT 'Hello, World!' LIKE 'Hello, %!'
1

expr [NOT] REGEXP pattern

Match an expression against a regular expression.

Parameters
  • pattern* — The regular expression to match against.

Examples

To check if a value matches the pattern ‘file-d+’:

;SELECT 'file-23' REGEXP 'file-\d+'
1

SELECT result-column FROM table WHERE [cond] GROUP BY grouping-expr ORDER BY ordering-term LIMIT limit-expr

Query the database and return zero or more rows of data.

Parameters
  • result-column — The expression used to generate a result for this column.

  • table — The table(s) to query for data

  • cond — The conditions used to select the rows to return.

  • grouping-expr — The expression to use when grouping rows.

  • ordering-term — The values to use when ordering the result set.

  • limit-expr — The maximum number of rows to return.

Examples

To select all of the columns from the table ‘syslog_log’:

;SELECT * FROM syslog_log
log_line log_time log_level log_hostname log_msgid log_pid log_pri log_procname log_struct log_syslog_tag syslog_version log_part log_idle_msecs log_mark log_comment log_tags log_annotations log_filters

INSERT INTO [schema-name.] table-name column-name VALUES expr

Insert rows into a table

Examples

To insert the pair containing ‘MSG’ and ‘HELLO, WORLD!’ into the ‘environ’ table:

;INSERT INTO environ VALUES ('MSG', 'HELLO, WORLD!')

OVER([base-window-name] PARTITION BY expr ORDER BY expr, [frame-spec])

Executes the preceding function over a window

Parameters
  • base-window-name — The name of the window definition

  • expr — The values to use for partitioning

  • expr — The values used to order the rows in the window

  • frame-spec — Determines which output rows are read by an aggregate window function


OVER window-name

Executes the preceding function over a window

Parameters
  • window-name* — The name of the window definition


UPDATE table SET column-name WHERE [cond]

Modify a subset of values in zero or more rows of the given table

Parameters
  • table* — The table to update

  • column-name — The columns in the table to update.

    • expr* — The values to place into the column.

  • cond — The condition used to determine whether a row should be updated.

Examples

To mark the syslog message at line 40:

;UPDATE syslog_log SET log_mark = 1 WHERE log_line = 40

abs(x)

Return the absolute value of the argument

Parameters
  • x* — The number to convert

Examples

To get the absolute value of -1:

;SELECT abs(-1)
1
See Also

acos(num), acosh(num), asin(num), asinh(num), atan2(y, x), atan(num), atanh(num), atn2(y, x), avg(X), ceil(num), degrees(radians), exp(x), floor(num), log10(x), log(x), max(X), min(X), pi(), power(base, exp), radians(degrees), round(num, [digits]), sign(num), square(num), sum(X), total(X)


acos(num)

Returns the arccosine of a number, in radians

Parameters
  • num* — A cosine value that is between -1 and 1

Examples

To get the arccosine of 0.2:

;SELECT acos(0.2)
1.3694384060045657
See Also

abs(x), acosh(num), asin(num), asinh(num), atan2(y, x), atan(num), atanh(num), atn2(y, x), avg(X), ceil(num), degrees(radians), exp(x), floor(num), log10(x), log(x), max(X), min(X), pi(), power(base, exp), radians(degrees), round(num, [digits]), sign(num), square(num), sum(X), total(X)


acosh(num)

Returns the hyperbolic arccosine of a number

Parameters
  • num* — A number that is one or more

Examples

To get the hyperbolic arccosine of 1.2:

;SELECT acosh(1.2)
0.6223625037147786
See Also

abs(x), acos(num), asin(num), asinh(num), atan2(y, x), atan(num), atanh(num), atn2(y, x), avg(X), ceil(num), degrees(radians), exp(x), floor(num), log10(x), log(x), max(X), min(X), pi(), power(base, exp), radians(degrees), round(num, [digits]), sign(num), square(num), sum(X), total(X)


anonymize(value)

Replace identifying information with random values.

PRQL Name: text.anonymize

Parameters
  • value* — The text to anonymize

Examples

To anonymize an IP address:

;SELECT anonymize('Hello, 192.168.1.2')
Aback, 10.0.0.1
See Also

char(X), charindex(needle, haystack, [start]), decode(value, algorithm), encode(value, algorithm), endswith(str, suffix), extract(str), group_concat(X, [sep]), group_spooky_hash(str), gunzip(b), gzip(value), humanize_duration(secs), humanize_file_size(value), humanize_id(id), instr(haystack, needle), leftstr(str, N), length(str), logfmt2json(str), lower(str), ltrim(str, [chars]), padc(str, len), padl(str, len), padr(str, len), parse_url(url), pretty_print(str), printf(format, X), proper(str), regexp_capture_into_json(string, pattern, [options]), regexp_capture(string, pattern), regexp_match(re, str), regexp_replace(str, re, repl), replace(str, old, replacement), replicate(str, N), reverse(str), rightstr(str, N), rtrim(str, [chars]), sparkline(value, [upper]), spooky_hash(str), startswith(str, prefix), strfilter(source, include), substr(str, start, [size]), timezone(tz, ts), trim(str, [chars]), unicode(X), unparse_url(obj), upper(str), xpath(xpath, xmldoc)


asin(num)

Returns the arcsine of a number, in radians

Parameters
  • num* — A sine value that is between -1 and 1

Examples

To get the arcsine of 0.2:

;SELECT asin(0.2)
0.2013579207903308
See Also

abs(x), acos(num), acosh(num), asinh(num), atan2(y, x), atan(num), atanh(num), atn2(y, x), avg(X), ceil(num), degrees(radians), exp(x), floor(num), log10(x), log(x), max(X), min(X), pi(), power(base, exp), radians(degrees), round(num, [digits]), sign(num), square(num), sum(X), total(X)


asinh(num)

Returns the hyperbolic arcsine of a number

Parameters
  • num* — The number

Examples

To get the hyperbolic arcsine of 0.2:

;SELECT asinh(0.2)
0.19869011034924142
See Also

abs(x), acos(num), acosh(num), asin(num), atan2(y, x), atan(num), atanh(num), atn2(y, x), avg(X), ceil(num), degrees(radians), exp(x), floor(num), log10(x), log(x), max(X), min(X), pi(), power(base, exp), radians(degrees), round(num, [digits]), sign(num), square(num), sum(X), total(X)


atan(num)

Returns the arctangent of a number, in radians

Parameters
  • num* — The number

Examples

To get the arctangent of 0.2:

;SELECT atan(0.2)
0.19739555984988078
See Also

abs(x), acos(num), acosh(num), asin(num), asinh(num), atan2(y, x), atanh(num), atn2(y, x), avg(X), ceil(num), degrees(radians), exp(x), floor(num), log10(x), log(x), max(X), min(X), pi(), power(base, exp), radians(degrees), round(num, [digits]), sign(num), square(num), sum(X), total(X)


atan2(y, x)

Returns the angle in the plane between the positive X axis and the ray from (0, 0) to the point (x, y)

Parameters
  • y* — The y coordinate of the point

  • x* — The x coordinate of the point

Examples

To get the angle, in degrees, for the point at (5, 5):

;SELECT degrees(atan2(5, 5))
45
See Also

abs(x), acos(num), acosh(num), asin(num), asinh(num), atan(num), atanh(num), atn2(y, x), avg(X), ceil(num), degrees(radians), exp(x), floor(num), log10(x), log(x), max(X), min(X), pi(), power(base, exp), radians(degrees), round(num, [digits]), sign(num), square(num), sum(X), total(X)


atanh(num)

Returns the hyperbolic arctangent of a number

Parameters
  • num* — The number

Examples

To get the hyperbolic arctangent of 0.2:

;SELECT atanh(0.2)
0.2027325540540822
See Also

abs(x), acos(num), acosh(num), asin(num), asinh(num), atan2(y, x), atan(num), atn2(y, x), avg(X), ceil(num), degrees(radians), exp(x), floor(num), log10(x), log(x), max(X), min(X), pi(), power(base, exp), radians(degrees), round(num, [digits]), sign(num), square(num), sum(X), total(X)


atn2(y, x)

Returns the angle in the plane between the positive X axis and the ray from (0, 0) to the point (x, y)

Parameters
  • y* — The y coordinate of the point

  • x* — The x coordinate of the point

Examples

To get the angle, in degrees, for the point at (5, 5):

;SELECT degrees(atn2(5, 5))
45
See Also

abs(x), acos(num), acosh(num), asin(num), asinh(num), atan2(y, x), atan(num), atanh(num), avg(X), ceil(num), degrees(radians), exp(x), floor(num), log10(x), log(x), max(X), min(X), pi(), power(base, exp), radians(degrees), round(num, [digits]), sign(num), square(num), sum(X), total(X)


avg(X)

Returns the average value of all non-NULL numbers within a group.

Parameters
  • X* — The value to compute the average of.

Examples

To get the average of the column ‘ex_duration’ from the table ‘lnav_example_log’:

;SELECT avg(ex_duration) FROM lnav_example_log
4.25

To get the average of the column ‘ex_duration’ from the table ‘lnav_example_log’ when grouped by ‘ex_procname’:

;SELECT ex_procname, avg(ex_duration) FROM lnav_example_log GROUP BY ex_procname
ex_procname avg(ex_ration)
gw                        5
hw                        2
See Also

abs(x), acos(num), acosh(num), asin(num), asinh(num), atan2(y, x), atan(num), atanh(num), atn2(y, x), ceil(num), degrees(radians), exp(x), floor(num), log10(x), log(x), max(X), min(X), pi(), power(base, exp), radians(degrees), round(num, [digits]), sign(num), square(num), sum(X), total(X)


basename(path)

Extract the base portion of a pathname.

PRQL Name: fs.basename

Parameters
  • path* — The path

Examples

To get the base of a plain file name:

;SELECT basename('foobar')
foobar

To get the base of a path:

;SELECT basename('foo/bar')
bar

To get the base of a directory:

;SELECT basename('foo/bar/')
bar

To get the base of an empty string:

;SELECT basename('')
.

To get the base of a Windows path:

;SELECT basename('foo\bar')
bar

To get the base of the root directory:

;SELECT basename('/')
/

To get the base of a path:

;from [{p='foo/bar'}] | select { fs.basename p }
bar
See Also

dirname(path), joinpath(path), readlink(path), realpath(path)


ceil(num)

Returns the smallest integer that is not less than the argument

Parameters
  • num* — The number to raise to the ceiling

Examples

To get the ceiling of 1.23:

;SELECT ceil(1.23)
2
See Also

abs(x), acos(num), acosh(num), asin(num), asinh(num), atan2(y, x), atan(num), atanh(num), atn2(y, x), avg(X), degrees(radians), exp(x), floor(num), log10(x), log(x), max(X), min(X), pi(), power(base, exp), radians(degrees), round(num, [digits]), sign(num), square(num), sum(X), total(X)


changes()

The number of database rows that were changed, inserted, or deleted by the most recent statement.


char(X)

Returns a string composed of characters having the given unicode code point values

Parameters
  • X — The unicode code point values

Examples

To get a string with the code points 0x48 and 0x49:

;SELECT char(0x48, 0x49)
HI
See Also

anonymize(value), charindex(needle, haystack, [start]), decode(value, algorithm), encode(value, algorithm), endswith(str, suffix), extract(str), group_concat(X, [sep]), group_spooky_hash(str), gunzip(b), gzip(value), humanize_duration(secs), humanize_file_size(value), humanize_id(id), instr(haystack, needle), leftstr(str, N), length(str), logfmt2json(str), lower(str), ltrim(str, [chars]), padc(str, len), padl(str, len), padr(str, len), parse_url(url), pretty_print(str), printf(format, X), proper(str), regexp_capture_into_json(string, pattern, [options]), regexp_capture(string, pattern), regexp_match(re, str), regexp_replace(str, re, repl), replace(str, old, replacement), replicate(str, N), reverse(str), rightstr(str, N), rtrim(str, [chars]), sparkline(value, [upper]), spooky_hash(str), startswith(str, prefix), strfilter(source, include), substr(str, start, [size]), timezone(tz, ts), trim(str, [chars]), unicode(X), unparse_url(obj), upper(str), xpath(xpath, xmldoc)


charindex(needle, haystack, [start])

Finds the first occurrence of the needle within the haystack and returns the number of prior characters plus 1, or 0 if Y is nowhere found within X

Parameters
  • needle* — The string to look for in the haystack

  • haystack* — The string to search within

  • start — The one-based index within the haystack to start the search

Examples

To search for the string ‘abc’ within ‘abcabc’ and starting at position 2:

;SELECT charindex('abc', 'abcabc', 2)
4

To search for the string ‘abc’ within ‘abcdef’ and starting at position 2:

;SELECT charindex('abc', 'abcdef', 2)
0
See Also

anonymize(value), char(X), decode(value, algorithm), encode(value, algorithm), endswith(str, suffix), extract(str), group_concat(X, [sep]), group_spooky_hash(str), gunzip(b), gzip(value), humanize_duration(secs), humanize_file_size(value), humanize_id(id), instr(haystack, needle), leftstr(str, N), length(str), logfmt2json(str), lower(str), ltrim(str, [chars]), padc(str, len), padl(str, len), padr(str, len), parse_url(url), pretty_print(str), printf(format, X), proper(str), regexp_capture_into_json(string, pattern, [options]), regexp_capture(string, pattern), regexp_match(re, str), regexp_replace(str, re, repl), replace(str, old, replacement), replicate(str, N), reverse(str), rightstr(str, N), rtrim(str, [chars]), sparkline(value, [upper]), spooky_hash(str), startswith(str, prefix), strfilter(source, include), substr(str, start, [size]), timezone(tz, ts), trim(str, [chars]), unicode(X), unparse_url(obj), upper(str), xpath(xpath, xmldoc)


coalesce(X, Y)

Returns a copy of its first non-NULL argument, or NULL if all arguments are NULL

Parameters
  • X* — A value to check for NULL-ness

  • Y — A value to check for NULL-ness

Examples

To get the first non-null value from three parameters:

;SELECT coalesce(null, 0, null)
0

count(X)

If the argument is ‘*’, the total number of rows in the group is returned. Otherwise, the number of times the argument is non-NULL.

Parameters
  • X* — The value to count.

Examples

To get the count of the non-NULL rows of ‘lnav_example_log’:

;SELECT count(*) FROM lnav_example_log
4

To get the count of the non-NULL values of ‘log_part’ from ‘lnav_example_log’:

;SELECT count(log_part) FROM lnav_example_log
2

cume_dist()


date(timestring, modifier)

Returns the date in this format: YYYY-MM-DD.

Parameters
  • timestring* — The string to convert to a date.

  • modifier — A transformation that is applied to the value to the left.

Examples

To get the date portion of the timestamp ‘2017-01-02T03:04:05’:

;SELECT date('2017-01-02T03:04:05')
2017-01-02

To get the date portion of the timestamp ‘2017-01-02T03:04:05’ plus one day:

;SELECT date('2017-01-02T03:04:05', '+1 day')
2017-01-03

To get the date portion of the epoch timestamp 1491341842:

;SELECT date(1491341842, 'unixepoch')
2017-04-04
See Also

datetime(timestring, modifier), humanize_duration(secs), julianday(timestring, modifier), strftime(format, timestring, modifier), time(timestring, modifier), timediff(time1, time2), timeslice(time, slice), timezone(tz, ts)


datetime(timestring, modifier)

Returns the date and time in this format: YYYY-MM-DD HH:MM:SS.

Parameters
  • timestring* — The string to convert to a date with time.

  • modifier — A transformation that is applied to the value to the left.

Examples

To get the date and time portion of the timestamp ‘2017-01-02T03:04:05’:

;SELECT datetime('2017-01-02T03:04:05')
2017-01-02 03:04:05

To get the date and time portion of the timestamp ‘2017-01-02T03:04:05’ plus one minute:

;SELECT datetime('2017-01-02T03:04:05', '+1 minute')
2017-01-02 03:05:05

To get the date and time portion of the epoch timestamp 1491341842:

;SELECT datetime(1491341842, 'unixepoch')
2017-04-04 21:37:22
See Also

date(timestring, modifier), humanize_duration(secs), julianday(timestring, modifier), strftime(format, timestring, modifier), time(timestring, modifier), timediff(time1, time2), timeslice(time, slice), timezone(tz, ts)


decode(value, algorithm)

Decode the value using the given algorithm

Parameters
  • value* — The value to decode

  • algorithm* — One of the following encoding algorithms: base64, hex, uri

Examples

To decode the URI-encoded string ‘%63%75%72%6c’:

;SELECT decode('%63%75%72%6c', 'uri')
curl
See Also

anonymize(value), char(X), charindex(needle, haystack, [start]), encode(value, algorithm), endswith(str, suffix), extract(str), group_concat(X, [sep]), group_spooky_hash(str), gunzip(b), gzip(value), humanize_duration(secs), humanize_file_size(value), humanize_id(id), instr(haystack, needle), leftstr(str, N), length(str), logfmt2json(str), lower(str), ltrim(str, [chars]), padc(str, len), padl(str, len), padr(str, len), parse_url(url), pretty_print(str), printf(format, X), proper(str), regexp_capture_into_json(string, pattern, [options]), regexp_capture(string, pattern), regexp_match(re, str), regexp_replace(str, re, repl), replace(str, old, replacement), replicate(str, N), reverse(str), rightstr(str, N), rtrim(str, [chars]), sparkline(value, [upper]), spooky_hash(str), startswith(str, prefix), strfilter(source, include), substr(str, start, [size]), timezone(tz, ts), trim(str, [chars]), unicode(X), unparse_url(obj), upper(str), xpath(xpath, xmldoc)


degrees(radians)

Converts radians to degrees

Parameters
  • radians* — The radians value to convert to degrees

Examples

To convert PI to degrees:

;SELECT degrees(pi())
180
See Also

abs(x), acos(num), acosh(num), asin(num), asinh(num), atan2(y, x), atan(num), atanh(num), atn2(y, x), avg(X), ceil(num), exp(x), floor(num), log10(x), log(x), max(X), min(X), pi(), power(base, exp), radians(degrees), round(num, [digits]), sign(num), square(num), sum(X), total(X)


dense_rank()


dirname(path)

Extract the directory portion of a pathname.

PRQL Name: fs.dirname

Parameters
  • path* — The path

Examples

To get the directory of a relative file path:

;SELECT dirname('foo/bar')
foo

To get the directory of an absolute file path:

;SELECT dirname('/foo/bar')
/foo

To get the directory of a file in the root directory:

;SELECT dirname('/bar')
/

To get the directory of a Windows path:

;SELECT dirname('foo\bar')
foo

To get the directory of an empty path:

;SELECT dirname('')
.
See Also

basename(path), joinpath(path), readlink(path), realpath(path)


echoln(value)


encode(value, algorithm)

Encode the value using the given algorithm

Parameters
  • value* — The value to encode

  • algorithm* — One of the following encoding algorithms: base64, hex, uri

Examples

To base64-encode ‘Hello, World!’:

;SELECT encode('Hello, World!', 'base64')
SGVsbG8sIFdvcmxkIQ==

To hex-encode ‘Hello, World!’:

;SELECT encode('Hello, World!', 'hex')
48656c6c6f2c20576f726c6421

To URI-encode ‘Hello, World!’:

;SELECT encode('Hello, World!', 'uri')
Hello%2C%20World%21
See Also

anonymize(value), char(X), charindex(needle, haystack, [start]), decode(value, algorithm), endswith(str, suffix), extract(str), group_concat(X, [sep]), group_spooky_hash(str), gunzip(b), gzip(value), humanize_duration(secs), humanize_file_size(value), humanize_id(id), instr(haystack, needle), leftstr(str, N), length(str), logfmt2json(str), lower(str), ltrim(str, [chars]), padc(str, len), padl(str, len), padr(str, len), parse_url(url), pretty_print(str), printf(format, X), proper(str), regexp_capture_into_json(string, pattern, [options]), regexp_capture(string, pattern), regexp_match(re, str), regexp_replace(str, re, repl), replace(str, old, replacement), replicate(str, N), reverse(str), rightstr(str, N), rtrim(str, [chars]), sparkline(value, [upper]), spooky_hash(str), startswith(str, prefix), strfilter(source, include), substr(str, start, [size]), timezone(tz, ts), trim(str, [chars]), unicode(X), unparse_url(obj), upper(str), xpath(xpath, xmldoc)


endswith(str, suffix)

Test if a string ends with the given suffix

Parameters
  • str* — The string to test

  • suffix* — The suffix to check in the string

Examples

To test if the string ‘notbad.jpg’ ends with ‘.jpg’:

;SELECT endswith('notbad.jpg', '.jpg')
1

To test if the string ‘notbad.png’ starts with ‘.jpg’:

;SELECT endswith('notbad.png', '.jpg')
0
See Also

anonymize(value), char(X), charindex(needle, haystack, [start]), decode(value, algorithm), encode(value, algorithm), extract(str), group_concat(X, [sep]), group_spooky_hash(str), gunzip(b), gzip(value), humanize_duration(secs), humanize_file_size(value), humanize_id(id), instr(haystack, needle), leftstr(str, N), length(str), logfmt2json(str), lower(str), ltrim(str, [chars]), padc(str, len), padl(str, len), padr(str, len), parse_url(url), pretty_print(str), printf(format, X), proper(str), regexp_capture_into_json(string, pattern, [options]), regexp_capture(string, pattern), regexp_match(re, str), regexp_replace(str, re, repl), replace(str, old, replacement), replicate(str, N), reverse(str), rightstr(str, N), rtrim(str, [chars]), sparkline(value, [upper]), spooky_hash(str), startswith(str, prefix), strfilter(source, include), substr(str, start, [size]), timezone(tz, ts), trim(str, [chars]), unicode(X), unparse_url(obj), upper(str), xpath(xpath, xmldoc)


exp(x)

Returns the value of e raised to the power of x

Parameters
  • x* — The exponent

Examples

To raise e to 2:

;SELECT exp(2)
7.38905609893065
See Also

abs(x), acos(num), acosh(num), asin(num), asinh(num), atan2(y, x), atan(num), atanh(num), atn2(y, x), avg(X), ceil(num), degrees(radians), floor(num), log10(x), log(x), max(X), min(X), pi(), power(base, exp), radians(degrees), round(num, [digits]), sign(num), square(num), sum(X), total(X)


extract(str)

Automatically Parse and extract data from a string

PRQL Name: text.discover

Parameters
  • str* — The string to parse

Examples

To extract key/value pairs from a string:

;SELECT extract('foo=1 bar=2 name="Rolo Tomassi"')
{"foo":1,"bar":2,"name":"Rolo Tomassi"}

To extract columnar data from a string:

;SELECT extract('1.0 abc 2.0')
{"col_0":1.0,"col_1":2.0}
See Also

anonymize(value), char(X), charindex(needle, haystack, [start]), decode(value, algorithm), encode(value, algorithm), endswith(str, suffix), group_concat(X, [sep]), group_spooky_hash(str), gunzip(b), gzip(value), humanize_duration(secs), humanize_file_size(value), humanize_id(id), instr(haystack, needle), leftstr(str, N), length(str), logfmt2json(str), lower(str), ltrim(str, [chars]), padc(str, len), padl(str, len), padr(str, len), parse_url(url), pretty_print(str), printf(format, X), proper(str), regexp_capture_into_json(string, pattern, [options]), regexp_capture(string, pattern), regexp_match(re, str), regexp_replace(str, re, repl), replace(str, old, replacement), replicate(str, N), reverse(str), rightstr(str, N), rtrim(str, [chars]), sparkline(value, [upper]), spooky_hash(str), startswith(str, prefix), strfilter(source, include), substr(str, start, [size]), timezone(tz, ts), trim(str, [chars]), unicode(X), unparse_url(obj), upper(str), xpath(xpath, xmldoc)


first_value(expr)

Returns the result of evaluating the expression against the first row in the window frame.

Parameters
  • expr* — The expression to execute over the first row

See Also

cume_dist(), dense_rank(), lag(expr, [offset], [default]), last_value(expr), lead(expr, [offset], [default]), nth_value(expr, N), ntile(groups), percent_rank(), rank(), row_number()


floor(num)

Returns the largest integer that is not greater than the argument

Parameters
  • num* — The number to lower to the floor

Examples

To get the floor of 1.23:

;SELECT floor(1.23)
1
See Also

abs(x), acos(num), acosh(num), asin(num), asinh(num), atan2(y, x), atan(num), atanh(num), atn2(y, x), avg(X), ceil(num), degrees(radians), exp(x), log10(x), log(x), max(X), min(X), pi(), power(base, exp), radians(degrees), round(num, [digits]), sign(num), square(num), sum(X), total(X)


fstat(pattern)

A table-valued function for getting information about file paths/globs

Parameters
  • pattern* — The file path or glob pattern to query.

Examples

To read a file and raise an error if there is a problem:

;SELECT ifnull(data, raise_error('cannot read: ' || st_name, error)) FROM fstat('/non-existent')
 error: cannot read: non-existent
 reason: No such file or directory
 --> command:1

generate_series(start, stop, [step])

A table-valued-function that returns the whole numbers between a lower and upper bound, inclusive

Parameters
  • start* — The starting point of the series

  • stop* — The stopping point of the series

  • step — The increment between each value

Examples

To generate the numbers in the range [10, 14]:

;SELECT value FROM generate_series(10, 14)
  value
        10
        11
        12
        13
        14

To generate every other number in the range [10, 14]:

;SELECT value FROM generate_series(10, 14, 2)
  value
        10
        12
        14

To count down from five to 1:

;SELECT value FROM generate_series(1, 5, -1)
  value
         5
         4
         3
         2
         1

gethostbyaddr(hostname)

Get the hostname for the given IP address

PRQL Name: net.gethostbyaddr

Parameters
  • hostname* — The IP address to lookup.

Examples

To get the hostname for the IP ‘127.0.0.1’:

;SELECT gethostbyaddr('127.0.0.1')
localhost
See Also

gethostbyname(hostname)


gethostbyname(hostname)

Get the IP address for the given hostname

PRQL Name: net.gethostbyname

Parameters
  • hostname* — The DNS hostname to lookup.

Examples

To get the IP address for ‘localhost’:

;SELECT gethostbyname('localhost')
127.0.0.1
See Also

gethostbyaddr(hostname)


glob(pattern, str)

Match a string against Unix glob pattern

Parameters
  • pattern* — The glob pattern

  • str* — The string to match

Examples

To test if the string ‘abc’ matches the glob ‘a*’:

;SELECT glob('a*', 'abc')
1

group_concat(X, [sep])

Returns a string which is the concatenation of all non-NULL values of X separated by a comma or the given separator.

Parameters
  • X* — The value to concatenate.

  • sep — The separator to place between the values.

Examples

To concatenate the values of the column ‘ex_procname’ from the table ‘lnav_example_log’:

;SELECT group_concat(ex_procname) FROM lnav_example_log
hw,gw,gw,gw

To join the values of the column ‘ex_procname’ using the string ‘, ‘:

;SELECT group_concat(ex_procname, ', ') FROM lnav_example_log
hw, gw, gw, gw

To concatenate the distinct values of the column ‘ex_procname’ from the table ‘lnav_example_log’:

;SELECT group_concat(DISTINCT ex_procname) FROM lnav_example_log
hw,gw
See Also

anonymize(value), char(X), charindex(needle, haystack, [start]), decode(value, algorithm), encode(value, algorithm), endswith(str, suffix), extract(str), group_spooky_hash(str), gunzip(b), gzip(value), humanize_duration(secs), humanize_file_size(value), humanize_id(id), instr(haystack, needle), leftstr(str, N), length(str), logfmt2json(str), lower(str), ltrim(str, [chars]), padc(str, len), padl(str, len), padr(str, len), parse_url(url), pretty_print(str), printf(format, X), proper(str), regexp_capture_into_json(string, pattern, [options]), regexp_capture(string, pattern), regexp_match(re, str), regexp_replace(str, re, repl), replace(str, old, replacement), replicate(str, N), reverse(str), rightstr(str, N), rtrim(str, [chars]), sparkline(value, [upper]), spooky_hash(str), startswith(str, prefix), strfilter(source, include), substr(str, start, [size]), timezone(tz, ts), trim(str, [chars]), unicode(X), unparse_url(obj), upper(str), xpath(xpath, xmldoc)


group_spooky_hash(str)

Compute the hash value for the given arguments

Parameters
  • str — The string to hash

Examples

To produce a hash of all of the values of ‘column1’:

;SELECT group_spooky_hash(column1) FROM (VALUES ('abc'), ('123'))
4e7a190aead058cb123c94290f29c34a
See Also

anonymize(value), char(X), charindex(needle, haystack, [start]), decode(value, algorithm), encode(value, algorithm), endswith(str, suffix), extract(str), group_concat(X, [sep]), gunzip(b), gzip(value), humanize_duration(secs), humanize_file_size(value), humanize_id(id), instr(haystack, needle), leftstr(str, N), length(str), logfmt2json(str), lower(str), ltrim(str, [chars]), padc(str, len), padl(str, len), padr(str, len), parse_url(url), pretty_print(str), printf(format, X), proper(str), regexp_capture_into_json(string, pattern, [options]), regexp_capture(string, pattern), regexp_match(re, str), regexp_replace(str, re, repl), replace(str, old, replacement), replicate(str, N), reverse(str), rightstr(str, N), rtrim(str, [chars]), sparkline(value, [upper]), spooky_hash(str), startswith(str, prefix), strfilter(source, include), substr(str, start, [size]), timezone(tz, ts), trim(str, [chars]), unicode(X), unparse_url(obj), upper(str), xpath(xpath, xmldoc)


gunzip(b)

Decompress a gzip file

Parameters
  • b — The blob to decompress

See Also

anonymize(value), char(X), charindex(needle, haystack, [start]), decode(value, algorithm), encode(value, algorithm), endswith(str, suffix), extract(str), group_concat(X, [sep]), group_spooky_hash(str), gzip(value), humanize_duration(secs), humanize_file_size(value), humanize_id(id), instr(haystack, needle), leftstr(str, N), length(str), logfmt2json(str), lower(str), ltrim(str, [chars]), padc(str, len), padl(str, len), padr(str, len), parse_url(url), pretty_print(str), printf(format, X), proper(str), regexp_capture_into_json(string, pattern, [options]), regexp_capture(string, pattern), regexp_match(re, str), regexp_replace(str, re, repl), replace(str, old, replacement), replicate(str, N), reverse(str), rightstr(str, N), rtrim(str, [chars]), sparkline(value, [upper]), spooky_hash(str), startswith(str, prefix), strfilter(source, include), substr(str, start, [size]), timezone(tz, ts), trim(str, [chars]), unicode(X), unparse_url(obj), upper(str), xpath(xpath, xmldoc)


gzip(value)

Compress a string into a gzip file

Parameters
  • value — The value to compress

See Also

anonymize(value), char(X), charindex(needle, haystack, [start]), decode(value, algorithm), encode(value, algorithm), endswith(str, suffix), extract(str), group_concat(X, [sep]), group_spooky_hash(str), gunzip(b), humanize_duration(secs), humanize_file_size(value), humanize_id(id), instr(haystack, needle), leftstr(str, N), length(str), logfmt2json(str), lower(str), ltrim(str, [chars]), padc(str, len), padl(str, len), padr(str, len), parse_url(url), pretty_print(str), printf(format, X), proper(str), regexp_capture_into_json(string, pattern, [options]), regexp_capture(string, pattern), regexp_match(re, str), regexp_replace(str, re, repl), replace(str, old, replacement), replicate(str, N), reverse(str), rightstr(str, N), rtrim(str, [chars]), sparkline(value, [upper]), spooky_hash(str), startswith(str, prefix), strfilter(source, include), substr(str, start, [size]), timezone(tz, ts), trim(str, [chars]), unicode(X), unparse_url(obj), upper(str), xpath(xpath, xmldoc)


hex(X)

Returns a string which is the upper-case hexadecimal rendering of the content of its argument.

Parameters
  • X* — The blob to convert to hexadecimal

Examples

To get the hexadecimal rendering of the string ‘abc’:

;SELECT hex('abc')
616263

humanize_duration(secs)

Format the given seconds value as an abbreviated duration string

PRQL Name: humanize.duration

Parameters
  • secs* — The duration in seconds

Examples

To format a duration:

;SELECT humanize_duration(15 * 60)
15m00s

To format a sub-second value:

;SELECT humanize_duration(1.5)
1s500
See Also

anonymize(value), char(X), charindex(needle, haystack, [start]), date(timestring, modifier), datetime(timestring, modifier), decode(value, algorithm), encode(value, algorithm), endswith(str, suffix), extract(str), group_concat(X, [sep]), group_spooky_hash(str), gunzip(b), gzip(value), humanize_file_size(value), humanize_id(id), instr(haystack, needle), julianday(timestring, modifier), leftstr(str, N), length(str), logfmt2json(str), lower(str), ltrim(str, [chars]), padc(str, len), padl(str, len), padr(str, len), parse_url(url), pretty_print(str), printf(format, X), proper(str), regexp_capture_into_json(string, pattern, [options]), regexp_capture(string, pattern), regexp_match(re, str), regexp_replace(str, re, repl), replace(str, old, replacement), replicate(str, N), reverse(str), rightstr(str, N), rtrim(str, [chars]), sparkline(value, [upper]), spooky_hash(str), startswith(str, prefix), strfilter(source, include), strftime(format, timestring, modifier), substr(str, start, [size]), time(timestring, modifier), timediff(time1, time2), timeslice(time, slice), timezone(tz, ts), timezone(tz, ts), trim(str, [chars]), unicode(X), unparse_url(obj), upper(str), xpath(xpath, xmldoc)


humanize_file_size(value)

Format the given file size as a human-friendly string

PRQL Name: humanize.file_size

Parameters
  • value* — The file size to format

Examples

To format an amount:

;SELECT humanize_file_size(10 * 1024 * 1024)
10.0MB
See Also

anonymize(value), char(X), charindex(needle, haystack, [start]), decode(value, algorithm), encode(value, algorithm), endswith(str, suffix), extract(str), group_concat(X, [sep]), group_spooky_hash(str), gunzip(b), gzip(value), humanize_duration(secs), humanize_id(id), instr(haystack, needle), leftstr(str, N), length(str), logfmt2json(str), lower(str), ltrim(str, [chars]), padc(str, len), padl(str, len), padr(str, len), parse_url(url), pretty_print(str), printf(format, X), proper(str), regexp_capture_into_json(string, pattern, [options]), regexp_capture(string, pattern), regexp_match(re, str), regexp_replace(str, re, repl), replace(str, old, replacement), replicate(str, N), reverse(str), rightstr(str, N), rtrim(str, [chars]), sparkline(value, [upper]), spooky_hash(str), startswith(str, prefix), strfilter(source, include), substr(str, start, [size]), timezone(tz, ts), trim(str, [chars]), unicode(X), unparse_url(obj), upper(str), xpath(xpath, xmldoc)


humanize_id(id)

Colorize the given ID using ANSI escape codes.

PRQL Name: humanize.id

Parameters
  • id* — The identifier to color

Examples

To colorize the ID ‘cluster1’:

;SELECT humanize_id('cluster1')
cluster1
See Also

anonymize(value), char(X), charindex(needle, haystack, [start]), decode(value, algorithm), encode(value, algorithm), endswith(str, suffix), extract(str), group_concat(X, [sep]), group_spooky_hash(str), gunzip(b), gzip(value), humanize_duration(secs), humanize_file_size(value), instr(haystack, needle), leftstr(str, N), length(str), logfmt2json(str), lower(str), ltrim(str, [chars]), padc(str, len), padl(str, len), padr(str, len), parse_url(url), pretty_print(str), printf(format, X), proper(str), regexp_capture_into_json(string, pattern, [options]), regexp_capture(string, pattern), regexp_match(re, str), regexp_replace(str, re, repl), replace(str, old, replacement), replicate(str, N), reverse(str), rightstr(str, N), rtrim(str, [chars]), sparkline(value, [upper]), spooky_hash(str), startswith(str, prefix), strfilter(source, include), substr(str, start, [size]), timezone(tz, ts), trim(str, [chars]), unicode(X), unparse_url(obj), upper(str), xpath(xpath, xmldoc)


ifnull(X, Y)

Returns a copy of its first non-NULL argument, or NULL if both arguments are NULL

Parameters
  • X* — A value to check for NULL-ness

  • Y* — A value to check for NULL-ness

Examples

To get the first non-null value between null and zero:

;SELECT ifnull(null, 0)
0

instr(haystack, needle)

Finds the first occurrence of the needle within the haystack and returns the number of prior characters plus 1, or 0 if the needle was not found

Parameters
  • haystack* — The string to search within

  • needle* — The string to look for in the haystack

Examples

To test get the position of ‘b’ in the string ‘abc’:

;SELECT instr('abc', 'b')
2
See Also

anonymize(value), char(X), charindex(needle, haystack, [start]), decode(value, algorithm), encode(value, algorithm), endswith(str, suffix), extract(str), group_concat(X, [sep]), group_spooky_hash(str), gunzip(b), gzip(value), humanize_duration(secs), humanize_file_size(value), humanize_id(id), leftstr(str, N), length(str), logfmt2json(str), lower(str), ltrim(str, [chars]), padc(str, len), padl(str, len), padr(str, len), parse_url(url), pretty_print(str), printf(format, X), proper(str), regexp_capture_into_json(string, pattern, [options]), regexp_capture(string, pattern), regexp_match(re, str), regexp_replace(str, re, repl), replace(str, old, replacement), replicate(str, N), reverse(str), rightstr(str, N), rtrim(str, [chars]), sparkline(value, [upper]), spooky_hash(str), startswith(str, prefix), strfilter(source, include), substr(str, start, [size]), timezone(tz, ts), trim(str, [chars]), unicode(X), unparse_url(obj), upper(str), xpath(xpath, xmldoc)


jget(json, ptr, [default])

Get the value from a JSON object using a JSON-Pointer.

PRQL Name: json.get

Parameters
  • json* — The JSON object to query.

  • ptr* — The JSON-Pointer to lookup in the object.

  • default — The default value if the value was not found

Examples

To get the root of a JSON value:

;SELECT jget('1', '')
1

To get the property named ‘b’ in a JSON object:

;SELECT jget('{ "a": 1, "b": 2 }', '/b')
2

To get the ‘msg’ property and return a default if it does not exist:

;SELECT jget(null, '/msg', 'Hello')
Hello
See Also

json_array_length(X, [P]), json_array(X), json_concat(json, value), json_contains(json, value), json_each(X, [P]), json_extract(X, P), json_group_array(value), json_group_object(name, value), json_insert(X, P, Y), json_object(N, V), json_quote(X), json_remove(X, P), json_replace(X, P, Y), json_set(X, P, Y), json_tree(X, [P]), json_type(X, [P]), json_valid(X), json(X), yaml_to_json(yaml)


joinpath(path)

Join components of a path together.

PRQL Name: fs.join

Parameters
  • path — One or more path components to join together. If an argument starts with a forward or backward slash, it will be considered an absolute path and any preceding elements will be ignored.

Examples

To join a directory and file name into a relative path:

;SELECT joinpath('foo', 'bar')
foo/bar

To join an empty component with other names into a relative path:

;SELECT joinpath('', 'foo', 'bar')
foo/bar

To create an absolute path with two path components:

;SELECT joinpath('/', 'foo', 'bar')
/foo/bar

To create an absolute path from a path component that starts with a forward slash:

;SELECT joinpath('/', 'foo', '/bar')
/bar
See Also

basename(path), dirname(path), readlink(path), realpath(path)


json(X)


json_array(X)

Constructs a JSON array from its arguments.

Parameters
  • X — The values of the JSON array

Examples

To create an array of all types:

;SELECT json_array(NULL, 1, 2.1, 'three', json_array(4), json_object('five', 'six'))
[null,1,2.1,"three",[4],{"five":"six"}]

To create an empty array:

;SELECT json_array()
[]
See Also

jget(json, ptr, [default]), json_array_length(X, [P]), json_concat(json, value), json_contains(json, value), json_each(X, [P]), json_extract(X, P), json_group_array(value), json_group_object(name, value), json_insert(X, P, Y), json_object(N, V), json_quote(X), json_remove(X, P), json_replace(X, P, Y), json_set(X, P, Y), json_tree(X, [P]), json_type(X, [P]), json_valid(X), json(X), yaml_to_json(yaml)


json_array_length(X, [P])

Returns the length of a JSON array.

Parameters
  • X* — The JSON object.

  • P — The path to the array in ‘X’.

Examples

To get the length of an array:

;SELECT json_array_length('[1, 2, 3]')
3

To get the length of a nested array:

;SELECT json_array_length('{"arr": [1, 2, 3]}', '$.arr')
3
See Also

jget(json, ptr, [default]), json_array(X), json_concat(json, value), json_contains(json, value), json_each(X, [P]), json_extract(X, P), json_group_array(value), json_group_object(name, value), json_insert(X, P, Y), json_object(N, V), json_quote(X), json_remove(X, P), json_replace(X, P, Y), json_set(X, P, Y), json_tree(X, [P]), json_type(X, [P]), json_valid(X), json(X), yaml_to_json(yaml)


json_concat(json, value)

Returns an array with the given values concatenated onto the end. If the initial value is null, the result will be an array with the given elements. If the initial value is an array, the result will be an array with the given values at the end. If the initial value is not null or an array, the result will be an array with two elements: the initial value and the given value.

PRQL Name: json.concat

Parameters
  • json* — The initial JSON value.

  • value — The value(s) to add to the end of the array.

Examples

To append the number 4 to null:

;SELECT json_concat(NULL, 4)
[4]

To append 4 and 5 to the array [1, 2, 3]:

;SELECT json_concat('[1, 2, 3]', 4, 5)
[1,2,3,4,5]

To concatenate two arrays together:

;SELECT json_concat('[1, 2, 3]', json('[4, 5]'))
[1,2,3,4,5]
See Also

jget(json, ptr, [default]), json_array_length(X, [P]), json_array(X), json_contains(json, value), json_each(X, [P]), json_extract(X, P), json_group_array(value), json_group_object(name, value), json_insert(X, P, Y), json_object(N, V), json_quote(X), json_remove(X, P), json_replace(X, P, Y), json_set(X, P, Y), json_tree(X, [P]), json_type(X, [P]), json_valid(X), json(X), yaml_to_json(yaml)


json_contains(json, value)

Check if a JSON value contains the given element.

PRQL Name: json.contains

Parameters
  • json* — The JSON value to query.

  • value* — The value to look for in the first argument

Examples

To test if a JSON array contains the number 4:

;SELECT json_contains('[1, 2, 3]', 4)
0

To test if a JSON array contains the string ‘def’:

;SELECT json_contains('["abc", "def"]', 'def')
1
See Also

jget(json, ptr, [default]), json_array_length(X, [P]), json_array(X), json_concat(json, value), json_each(X, [P]), json_extract(X, P), json_group_array(value), json_group_object(name, value), json_insert(X, P, Y), json_object(N, V), json_quote(X), json_remove(X, P), json_replace(X, P, Y), json_set(X, P, Y), json_tree(X, [P]), json_type(X, [P]), json_valid(X), json(X), yaml_to_json(yaml)


json_each(X, [P])

A table-valued-function that returns the children of the top-level JSON value

Parameters
  • X* — The JSON value to query

  • P — The path to the value to query

Examples

To iterate over an array:

;SELECT * FROM json_each('[null,1,"two",{"three":4.5}]')
key     value      type    atom  id parent fullkey path
  0 <NULL>        null    <NULL>  2 <NULL> $[0]    $
  1 1             integer 1       3 <NULL> $[1]    $
  2 two           text    two     5 <NULL> $[2]    $
  3 {"three":4.5} object  <NULL>  9 <NULL> $[3]    $
See Also

jget(json, ptr, [default]), json_array_length(X, [P]), json_array(X), json_concat(json, value), json_contains(json, value), json_extract(X, P), json_group_array(value), json_group_object(name, value), json_insert(X, P, Y), json_object(N, V), json_quote(X), json_remove(X, P), json_replace(X, P, Y), json_set(X, P, Y), json_tree(X, [P]), json_type(X, [P]), json_valid(X), json(X), yaml_to_json(yaml)


json_extract(X, P)

Returns the value(s) from the given JSON at the given path(s).

Parameters
  • X* — The JSON value.

  • P — The path to extract.

Examples

To get a number:

;SELECT json_extract('{"num": 1}', '$.num')
1

To get two numbers:

;SELECT json_extract('{"num": 1, "val": 2}', '$.num', '$.val')
[1,2]

To get an object:

;SELECT json_extract('{"obj": {"sub": 1}}', '$.obj')
{"sub":1}
See Also

jget(json, ptr, [default]), json_array_length(X, [P]), json_array(X), json_concat(json, value), json_contains(json, value), json_each(X, [P]), json_group_array(value), json_group_object(name, value), json_insert(X, P, Y), json_object(N, V), json_quote(X), json_remove(X, P), json_replace(X, P, Y), json_set(X, P, Y), json_tree(X, [P]), json_type(X, [P]), json_valid(X), json(X), yaml_to_json(yaml)


json_group_array(value)

Collect the given values from a query into a JSON array

PRQL Name: json.group_array

Parameters
  • value — The values to append to the array

Examples

To create an array from arguments:

;SELECT json_group_array('one', 2, 3.4)
["one",2,3.3999999999999999112]

To create an array from a column of values:

;SELECT json_group_array(column1) FROM (VALUES (1), (2), (3))
[1,2,3]
See Also

jget(json, ptr, [default]), json_array_length(X, [P]), json_array(X), json_concat(json, value), json_contains(json, value), json_each(X, [P]), json_extract(X, P), json_group_object(name, value), json_insert(X, P, Y), json_object(N, V), json_quote(X), json_remove(X, P), json_replace(X, P, Y), json_set(X, P, Y), json_tree(X, [P]), json_type(X, [P]), json_valid(X), json(X), yaml_to_json(yaml)


json_group_object(name, value)

Collect the given values from a query into a JSON object

PRQL Name: json.group_object

Parameters
  • name* — The property name for the value

  • value — The value to add to the object

Examples

To create an object from arguments:

;SELECT json_group_object('a', 1, 'b', 2)
{"a":1,"b":2}

To create an object from a pair of columns:

;SELECT json_group_object(column1, column2) FROM (VALUES ('a', 1), ('b', 2))
{"a":1,"b":2}
See Also

jget(json, ptr, [default]), json_array_length(X, [P]), json_array(X), json_concat(json, value), json_contains(json, value), json_each(X, [P]), json_extract(X, P), json_group_array(value), json_insert(X, P, Y), json_object(N, V), json_quote(X), json_remove(X, P), json_replace(X, P, Y), json_set(X, P, Y), json_tree(X, [P]), json_type(X, [P]), json_valid(X), json(X), yaml_to_json(yaml)


json_insert(X, P, Y)

Inserts values into a JSON object/array at the given locations, if it does not already exist

Parameters
  • X* — The JSON value to update

  • P* — The path to the insertion point. A ‘#’ array index means append the value

  • Y* — The value to insert

Examples

To append to an array:

;SELECT json_insert('[1, 2]', '$[#]', 3)
[1,2,3]

To update an object:

;SELECT json_insert('{"a": 1}', '$.b', 2)
{"a":1,"b":2}

To ensure a value is set:

;SELECT json_insert('{"a": 1}', '$.a', 2)
{"a":1}

To update multiple values:

;SELECT json_insert('{"a": 1}', '$.b', 2, '$.c', 3)
{"a":1,"b":2,"c":3}
See Also

jget(json, ptr, [default]), json_array_length(X, [P]), json_array(X), json_concat(json, value), json_contains(json, value), json_each(X, [P]), json_extract(X, P), json_group_array(value), json_group_object(name, value), json_object(N, V), json_quote(X), json_remove(X, P), json_replace(X, P, Y), json_set(X, P, Y), json_tree(X, [P]), json_type(X, [P]), json_valid(X), json(X), yaml_to_json(yaml)


json_object(N, V)

Create a JSON object from the given arguments

Parameters
  • N* — The property name

  • V* — The property value

Examples

To create an object:

;SELECT json_object('a', 1, 'b', 'c')
{"a":1,"b":"c"}

To create an empty object:

;SELECT json_object()
{}
See Also

jget(json, ptr, [default]), json_array_length(X, [P]), json_array(X), json_concat(json, value), json_contains(json, value), json_each(X, [P]), json_extract(X, P), json_group_array(value), json_group_object(name, value), json_insert(X, P, Y), json_quote(X), json_remove(X, P), json_replace(X, P, Y), json_set(X, P, Y), json_tree(X, [P]), json_type(X, [P]), json_valid(X), json(X), yaml_to_json(yaml)


json_quote(X)

Returns the JSON representation of the given value, if it is not already JSON

Parameters
  • X* — The value to convert

Examples

To convert a string:

;SELECT json_quote('Hello, World!')
"Hello, World!"

To pass through an existing JSON value:

;SELECT json_quote(json('"Hello, World!"'))
"Hello, World!"
See Also

jget(json, ptr, [default]), json_array_length(X, [P]), json_array(X), json_concat(json, value), json_contains(json, value), json_each(X, [P]), json_extract(X, P), json_group_array(value), json_group_object(name, value), json_insert(X, P, Y), json_object(N, V), json_remove(X, P), json_replace(X, P, Y), json_set(X, P, Y), json_tree(X, [P]), json_type(X, [P]), json_valid(X), json(X), yaml_to_json(yaml)


json_remove(X, P)

Removes paths from a JSON value

Parameters
  • X* — The JSON value to update

  • P — The paths to remove

Examples

To remove elements of an array:

;SELECT json_remove('[1,2,3]', '$[1]', '$[1]')
[1]

To remove object properties:

;SELECT json_remove('{"a":1,"b":2}', '$.b')
{"a":1}
See Also

jget(json, ptr, [default]), json_array_length(X, [P]), json_array(X), json_concat(json, value), json_contains(json, value), json_each(X, [P]), json_extract(X, P), json_group_array(value), json_group_object(name, value), json_insert(X, P, Y), json_object(N, V), json_quote(X), json_replace(X, P, Y), json_set(X, P, Y), json_tree(X, [P]), json_type(X, [P]), json_valid(X), json(X), yaml_to_json(yaml)


json_replace(X, P, Y)

Replaces existing values in a JSON object/array at the given locations

Parameters
  • X* — The JSON value to update

  • P* — The path to replace

  • Y* — The new value for the property

Examples

To replace an existing value:

;SELECT json_replace('{"a": 1}', '$.a', 2)
{"a":2}

To replace a value without creating a new property:

;SELECT json_replace('{"a": 1}', '$.a', 2, '$.b', 3)
{"a":2}
See Also

jget(json, ptr, [default]), json_array_length(X, [P]), json_array(X), json_concat(json, value), json_contains(json, value), json_each(X, [P]), json_extract(X, P), json_group_array(value), json_group_object(name, value), json_insert(X, P, Y), json_object(N, V), json_quote(X), json_remove(X, P), json_set(X, P, Y), json_tree(X, [P]), json_type(X, [P]), json_valid(X), json(X), yaml_to_json(yaml)


json_set(X, P, Y)

Inserts or replaces existing values in a JSON object/array at the given locations

Parameters
  • X* — The JSON value to update

  • P* — The path to the insertion point. A ‘#’ array index means append the value

  • Y* — The value to set

Examples

To replace an existing array element:

;SELECT json_set('[1, 2]', '$[1]', 3)
[1,3]

To replace a value and create a new property:

;SELECT json_set('{"a": 1}', '$.a', 2, '$.b', 3)
{"a":2,"b":3}
See Also

jget(json, ptr, [default]), json_array_length(X, [P]), json_array(X), json_concat(json, value), json_contains(json, value), json_each(X, [P]), json_extract(X, P), json_group_array(value), json_group_object(name, value), json_insert(X, P, Y), json_object(N, V), json_quote(X), json_remove(X, P), json_replace(X, P, Y), json_tree(X, [P]), json_type(X, [P]), json_valid(X), json(X), yaml_to_json(yaml)


json_tree(X, [P])

A table-valued-function that recursively descends through a JSON value

Parameters
  • X* — The JSON value to query

  • P — The path to the value to query

Examples

To iterate over an array:

;SELECT key,value,type,atom,fullkey,path FROM json_tree('[null,1,"two",{"three":4.5}]')
 key        value       type    atom   fullkey   path
<NULL> [null,1":4.5}] array   <NULL> $          $
0      <NULL>          null    <NULL> $[0]       $
1      1               integer 1      $[1]       $
2      two             text    two    $[2]       $
3      {"three":4.5}   object  <NULL> $[3]       $
three  4.5             real    4.5    $[3].three $[3]
See Also

jget(json, ptr, [default]), json_array_length(X, [P]), json_array(X), json_concat(json, value), json_contains(json, value), json_each(X, [P]), json_extract(X, P), json_group_array(value), json_group_object(name, value), json_insert(X, P, Y), json_object(N, V), json_quote(X), json_remove(X, P), json_replace(X, P, Y), json_set(X, P, Y), json_type(X, [P]), json_valid(X), json(X), yaml_to_json(yaml)


json_type(X, [P])

Returns the type of a JSON value

Parameters
  • X* — The JSON value to query

  • P — The path to the value

Examples

To get the type of a value:

;SELECT json_type('[null,1,2.1,"three",{"four":5}]')
array

To get the type of an array element:

;SELECT json_type('[null,1,2.1,"three",{"four":5}]', '$[0]')
null

To get the type of a string:

;SELECT json_type('[null,1,2.1,"three",{"four":5}]', '$[3]')
text
See Also

jget(json, ptr, [default]), json_array_length(X, [P]), json_array(X), json_concat(json, value), json_contains(json, value), json_each(X, [P]), json_extract(X, P), json_group_array(value), json_group_object(name, value), json_insert(X, P, Y), json_object(N, V), json_quote(X), json_remove(X, P), json_replace(X, P, Y), json_set(X, P, Y), json_tree(X, [P]), json_valid(X), json(X), yaml_to_json(yaml)


json_valid(X)


julianday(timestring, modifier)

Returns the number of days since noon in Greenwich on November 24, 4714 B.C.

Parameters
  • timestring* — The string to convert to a date with time.

  • modifier — A transformation that is applied to the value to the left.

Examples

To get the julian day from the timestamp ‘2017-01-02T03:04:05’:

;SELECT julianday('2017-01-02T03:04:05')
2457755.627835648

To get the julian day from the timestamp ‘2017-01-02T03:04:05’ plus one minute:

;SELECT julianday('2017-01-02T03:04:05', '+1 minute')
2457755.6285300925

To get the julian day from the timestamp 1491341842:

;SELECT julianday(1491341842, 'unixepoch')
2457848.400949074
See Also

date(timestring, modifier), datetime(timestring, modifier), humanize_duration(secs), strftime(format, timestring, modifier), time(timestring, modifier), timediff(time1, time2), timeslice(time, slice), timezone(tz, ts)


lag(expr, [offset], [default])

Returns the result of evaluating the expression against the previous row in the partition.

Parameters
  • expr* — The expression to execute over the previous row

  • offset — The offset from the current row in the partition

  • default — The default value if the previous row does not exist instead of NULL

See Also

cume_dist(), dense_rank(), first_value(expr), last_value(expr), lead(expr, [offset], [default]), nth_value(expr, N), ntile(groups), percent_rank(), rank(), row_number()


last_insert_rowid()

Returns the ROWID of the last row insert from the database connection which invoked the function


last_value(expr)

Returns the result of evaluating the expression against the last row in the window frame.

Parameters
  • expr* — The expression to execute over the last row

See Also

cume_dist(), dense_rank(), first_value(expr), lag(expr, [offset], [default]), lead(expr, [offset], [default]), nth_value(expr, N), ntile(groups), percent_rank(), rank(), row_number()


lead(expr, [offset], [default])

Returns the result of evaluating the expression against the next row in the partition.

Parameters
  • expr* — The expression to execute over the next row

  • offset — The offset from the current row in the partition

  • default — The default value if the next row does not exist instead of NULL

See Also

cume_dist(), dense_rank(), first_value(expr), lag(expr, [offset], [default]), last_value(expr), nth_value(expr, N), ntile(groups), percent_rank(), rank(), row_number()


leftstr(str, N)

Returns the N leftmost (UTF-8) characters in the given string.

Parameters
  • str* — The string to return subset.

  • N* — The number of characters from the left side of the string to return.

Examples

To get the first character of the string ‘abc’:

;SELECT leftstr('abc', 1)
a

To get the first ten characters of a string, regardless of size:

;SELECT leftstr('abc', 10)
abc
See Also

anonymize(value), char(X), charindex(needle, haystack, [start]), decode(value, algorithm), encode(value, algorithm), endswith(str, suffix), extract(str), group_concat(X, [sep]), group_spooky_hash(str), gunzip(b), gzip(value), humanize_duration(secs), humanize_file_size(value), humanize_id(id), instr(haystack, needle), length(str), logfmt2json(str), lower(str), ltrim(str, [chars]), padc(str, len), padl(str, len), padr(str, len), parse_url(url), pretty_print(str), printf(format, X), proper(str), regexp_capture_into_json(string, pattern, [options]), regexp_capture(string, pattern), regexp_match(re, str), regexp_replace(str, re, repl), replace(str, old, replacement), replicate(str, N), reverse(str), rightstr(str, N), rtrim(str, [chars]), sparkline(value, [upper]), spooky_hash(str), startswith(str, prefix), strfilter(source, include), substr(str, start, [size]), timezone(tz, ts), trim(str, [chars]), unicode(X), unparse_url(obj), upper(str), xpath(xpath, xmldoc)


length(str)

Returns the number of characters (not bytes) in the given string prior to the first NUL character

Parameters
  • str* — The string to determine the length of

Examples

To get the length of the string ‘abc’:

;SELECT length('abc')
3
See Also

anonymize(value), char(X), charindex(needle, haystack, [start]), decode(value, algorithm), encode(value, algorithm), endswith(str, suffix), extract(str), group_concat(X, [sep]), group_spooky_hash(str), gunzip(b), gzip(value), humanize_duration(secs), humanize_file_size(value), humanize_id(id), instr(haystack, needle), leftstr(str, N), logfmt2json(str), lower(str), ltrim(str, [chars]), padc(str, len), padl(str, len), padr(str, len), parse_url(url), pretty_print(str), printf(format, X), proper(str), regexp_capture_into_json(string, pattern, [options]), regexp_capture(string, pattern), regexp_match(re, str), regexp_replace(str, re, repl), replace(str, old, replacement), replicate(str, N), reverse(str), rightstr(str, N), rtrim(str, [chars]), sparkline(value, [upper]), spooky_hash(str), startswith(str, prefix), strfilter(source, include), substr(str, start, [size]), timezone(tz, ts), trim(str, [chars]), unicode(X), unparse_url(obj), upper(str), xpath(xpath, xmldoc)


like(pattern, str, [escape])

Match a string against a pattern

Parameters
  • pattern* — The pattern to match. A percent symbol (%) will match zero or more characters and an underscore (_) will match a single character.

  • str* — The string to match

  • escape — The escape character that can be used to prefix a literal percent or underscore in the pattern.

Examples

To test if the string ‘aabcc’ contains the letter ‘b’:

;SELECT like('%b%', 'aabcc')
1

To test if the string ‘aab%’ ends with ‘b%’:

;SELECT like('%b:%', 'aab%', ':')
1

likelihood(value, probability)

Provides a hint to the query planner that the first argument is a boolean that is true with the given probability

Parameters
  • value* — The boolean value to return

  • probability* — A floating point constant between 0.0 and 1.0


likely(value)

Short-hand for likelihood(X,0.9375)

Parameters
  • value* — The boolean value to return


load_extension(path, [entry-point])

Loads SQLite extensions out of the given shared library file using the given entry point.

Parameters
  • path* — The path to the shared library containing the extension.


log(x)

Returns the natural logarithm of x

Parameters
  • x* — The number

Examples

To get the natual logarithm of 8:

;SELECT log(8)
2.0794415416798357
See Also

abs(x), acos(num), acosh(num), asin(num), asinh(num), atan2(y, x), atan(num), atanh(num), atn2(y, x), avg(X), ceil(num), degrees(radians), exp(x), floor(num), log10(x), max(X), min(X), pi(), power(base, exp), radians(degrees), round(num, [digits]), sign(num), square(num), sum(X), total(X)


log10(x)

Returns the base-10 logarithm of X

Parameters
  • x* — The number

Examples

To get the logarithm of 100:

;SELECT log10(100)
2
See Also

abs(x), acos(num), acosh(num), asin(num), asinh(num), atan2(y, x), atan(num), atanh(num), atn2(y, x), avg(X), ceil(num), degrees(radians), exp(x), floor(num), log(x), max(X), min(X), pi(), power(base, exp), radians(degrees), round(num, [digits]), sign(num), square(num), sum(X), total(X)


log_msg_line()

Return the starting line number of the focused log message.

PRQL Name: lnav.view.msg_line


log_top_datetime()

Return the timestamp of the line at the top of the log view.

PRQL Name: lnav.view.top_datetime


log_top_line()

Return the number of the focused line of the log view.

PRQL Name: lnav.view.top_line


logfmt2json(str)

Convert a logfmt-encoded string into JSON

PRQL Name: logfmt.to_json

Parameters
  • str* — The logfmt message to parse

Examples

To extract key/value pairs from a log message:

;SELECT logfmt2json('foo=1 bar=2 name="Rolo Tomassi"')
{"foo":1,"bar":2,"name":"Rolo Tomassi"}
See Also

anonymize(value), char(X), charindex(needle, haystack, [start]), decode(value, algorithm), encode(value, algorithm), endswith(str, suffix), extract(str), group_concat(X, [sep]), group_spooky_hash(str), gunzip(b), gzip(value), humanize_duration(secs), humanize_file_size(value), humanize_id(id), instr(haystack, needle), leftstr(str, N), length(str), lower(str), ltrim(str, [chars]), padc(str, len), padl(str, len), padr(str, len), parse_url(url), pretty_print(str), printf(format, X), proper(str), regexp_capture_into_json(string, pattern, [options]), regexp_capture(string, pattern), regexp_match(re, str), regexp_replace(str, re, repl), replace(str, old, replacement), replicate(str, N), reverse(str), rightstr(str, N), rtrim(str, [chars]), sparkline(value, [upper]), spooky_hash(str), startswith(str, prefix), strfilter(source, include), substr(str, start, [size]), timezone(tz, ts), trim(str, [chars]), unicode(X), unparse_url(obj), upper(str), xpath(xpath, xmldoc)


lower(str)

Returns a copy of the given string with all ASCII characters converted to lower case.

Parameters
  • str* — The string to convert.

Examples

To lowercase the string ‘AbC’:

;SELECT lower('AbC')
abc
See Also

anonymize(value), char(X), charindex(needle, haystack, [start]), decode(value, algorithm), encode(value, algorithm), endswith(str, suffix), extract(str), group_concat(X, [sep]), group_spooky_hash(str), gunzip(b), gzip(value), humanize_duration(secs), humanize_file_size(value), humanize_id(id), instr(haystack, needle), leftstr(str, N), length(str), logfmt2json(str), ltrim(str, [chars]), padc(str, len), padl(str, len), padr(str, len), parse_url(url), pretty_print(str), printf(format, X), proper(str), regexp_capture_into_json(string, pattern, [options]), regexp_capture(string, pattern), regexp_match(re, str), regexp_replace(str, re, repl), replace(str, old, replacement), replicate(str, N), reverse(str), rightstr(str, N), rtrim(str, [chars]), sparkline(value, [upper]), spooky_hash(str), startswith(str, prefix), strfilter(source, include), substr(str, start, [size]), timezone(tz, ts), trim(str, [chars]), unicode(X), unparse_url(obj), upper(str), xpath(xpath, xmldoc)


ltrim(str, [chars])

Returns a string formed by removing any and all characters that appear in the second argument from the left side of the first.

Parameters
  • str* — The string to trim characters from the left side

  • chars — The characters to trim. Defaults to spaces.

Examples

To trim the leading space characters from the string ‘ abc’:

;SELECT ltrim('   abc')
abc

To trim the characters ‘a’ or ‘b’ from the left side of the string ‘aaaabbbc’:

;SELECT ltrim('aaaabbbc', 'ab')
c
See Also

anonymize(value), char(X), charindex(needle, haystack, [start]), decode(value, algorithm), encode(value, algorithm), endswith(str, suffix), extract(str), group_concat(X, [sep]), group_spooky_hash(str), gunzip(b), gzip(value), humanize_duration(secs), humanize_file_size(value), humanize_id(id), instr(haystack, needle), leftstr(str, N), length(str), logfmt2json(str), lower(str), padc(str, len), padl(str, len), padr(str, len), parse_url(url), pretty_print(str), printf(format, X), proper(str), regexp_capture_into_json(string, pattern, [options]), regexp_capture(string, pattern), regexp_match(re, str), regexp_replace(str, re, repl), replace(str, old, replacement), replicate(str, N), reverse(str), rightstr(str, N), rtrim(str, [chars]), sparkline(value, [upper]), spooky_hash(str), startswith(str, prefix), strfilter(source, include), substr(str, start, [size]), timezone(tz, ts), trim(str, [chars]), unicode(X), unparse_url(obj), upper(str), xpath(xpath, xmldoc)


max(X)

Returns the argument with the maximum value, or return NULL if any argument is NULL.

Parameters
  • X — The numbers to find the maximum of. If only one argument is given, this function operates as an aggregate.

Examples

To get the largest value from the parameters:

;SELECT max(2, 1, 3)
3

To get the largest value from an aggregate:

;SELECT max(status) FROM http_status_codes
511
See Also

abs(x), acos(num), acosh(num), asin(num), asinh(num), atan2(y, x), atan(num), atanh(num), atn2(y, x), avg(X), ceil(num), degrees(radians), exp(x), floor(num), log10(x), log(x), min(X), pi(), power(base, exp), radians(degrees), round(num, [digits]), sign(num), square(num), sum(X), total(X)


min(X)

Returns the argument with the minimum value, or return NULL if any argument is NULL.

Parameters
  • X — The numbers to find the minimum of. If only one argument is given, this function operates as an aggregate.

Examples

To get the smallest value from the parameters:

;SELECT min(2, 1, 3)
1

To get the smallest value from an aggregate:

;SELECT min(status) FROM http_status_codes
100
See Also

abs(x), acos(num), acosh(num), asin(num), asinh(num), atan2(y, x), atan(num), atanh(num), atn2(y, x), avg(X), ceil(num), degrees(radians), exp(x), floor(num), log10(x), log(x), max(X), pi(), power(base, exp), radians(degrees), round(num, [digits]), sign(num), square(num), sum(X), total(X)


nth_value(expr, N)

Returns the result of evaluating the expression against the nth row in the window frame.

Parameters
  • expr* — The expression to execute over the nth row

  • N* — The row number

See Also

cume_dist(), dense_rank(), first_value(expr), lag(expr, [offset], [default]), last_value(expr), lead(expr, [offset], [default]), ntile(groups), percent_rank(), rank(), row_number()


ntile(groups)

Returns the number of the group that the current row is a part of

Parameters
  • groups* — The number of groups

See Also

cume_dist(), dense_rank(), first_value(expr), lag(expr, [offset], [default]), last_value(expr), lead(expr, [offset], [default]), nth_value(expr, N), percent_rank(), rank(), row_number()


nullif(X, Y)

Returns its first argument if the arguments are different and NULL if the arguments are the same.

Parameters
  • X* — The first argument to compare.

  • Y* — The argument to compare against the first.

Examples

To test if 1 is different from 1:

;SELECT nullif(1, 1)
<NULL>

To test if 1 is different from 2:

;SELECT nullif(1, 2)
1

padc(str, len)

Pad the given string with enough spaces to make it centered within the given length

Parameters
  • str* — The string to pad

  • len* — The minimum desired length of the output string

Examples

To pad the string ‘abc’ to a length of six characters:

;SELECT padc('abc', 6) || 'def'
 abc  def

To pad the string ‘abcdef’ to a length of eight characters:

;SELECT padc('abcdef', 8) || 'ghi'
 abcdef ghi
See Also

anonymize(value), char(X), charindex(needle, haystack, [start]), decode(value, algorithm), encode(value, algorithm), endswith(str, suffix), extract(str), group_concat(X, [sep]), group_spooky_hash(str), gunzip(b), gzip(value), humanize_duration(secs), humanize_file_size(value), humanize_id(id), instr(haystack, needle), leftstr(str, N), length(str), logfmt2json(str), lower(str), ltrim(str, [chars]), padl(str, len), padr(str, len), parse_url(url), pretty_print(str), printf(format, X), proper(str), regexp_capture_into_json(string, pattern, [options]), regexp_capture(string, pattern), regexp_match(re, str), regexp_replace(str, re, repl), replace(str, old, replacement), replicate(str, N), reverse(str), rightstr(str, N), rtrim(str, [chars]), sparkline(value, [upper]), spooky_hash(str), startswith(str, prefix), strfilter(source, include), substr(str, start, [size]), timezone(tz, ts), trim(str, [chars]), unicode(X), unparse_url(obj), upper(str), xpath(xpath, xmldoc)


padl(str, len)

Pad the given string with leading spaces until it reaches the desired length

Parameters
  • str* — The string to pad

  • len* — The minimum desired length of the output string

Examples

To pad the string ‘abc’ to a length of six characters:

;SELECT padl('abc', 6)
   abc

To pad the string ‘abcdef’ to a length of four characters:

;SELECT padl('abcdef', 4)
abcdef
See Also

anonymize(value), char(X), charindex(needle, haystack, [start]), decode(value, algorithm), encode(value, algorithm), endswith(str, suffix), extract(str), group_concat(X, [sep]), group_spooky_hash(str), gunzip(b), gzip(value), humanize_duration(secs), humanize_file_size(value), humanize_id(id), instr(haystack, needle), leftstr(str, N), length(str), logfmt2json(str), lower(str), ltrim(str, [chars]), padc(str, len), padr(str, len), parse_url(url), pretty_print(str), printf(format, X), proper(str), regexp_capture_into_json(string, pattern, [options]), regexp_capture(string, pattern), regexp_match(re, str), regexp_replace(str, re, repl), replace(str, old, replacement), replicate(str, N), reverse(str), rightstr(str, N), rtrim(str, [chars]), sparkline(value, [upper]), spooky_hash(str), startswith(str, prefix), strfilter(source, include), substr(str, start, [size]), timezone(tz, ts), trim(str, [chars]), unicode(X), unparse_url(obj), upper(str), xpath(xpath, xmldoc)


padr(str, len)

Pad the given string with trailing spaces until it reaches the desired length

Parameters
  • str* — The string to pad

  • len* — The minimum desired length of the output string

Examples

To pad the string ‘abc’ to a length of six characters:

;SELECT padr('abc', 6) || 'def'
abc   def

To pad the string ‘abcdef’ to a length of four characters:

;SELECT padr('abcdef', 4) || 'ghi'
abcdefghi
See Also

anonymize(value), char(X), charindex(needle, haystack, [start]), decode(value, algorithm), encode(value, algorithm), endswith(str, suffix), extract(str), group_concat(X, [sep]), group_spooky_hash(str), gunzip(b), gzip(value), humanize_duration(secs), humanize_file_size(value), humanize_id(id), instr(haystack, needle), leftstr(str, N), length(str), logfmt2json(str), lower(str), ltrim(str, [chars]), padc(str, len), padl(str, len), parse_url(url), pretty_print(str), printf(format, X), proper(str), regexp_capture_into_json(string, pattern, [options]), regexp_capture(string, pattern), regexp_match(re, str), regexp_replace(str, re, repl), replace(str, old, replacement), replicate(str, N), reverse(str), rightstr(str, N), rtrim(str, [chars]), sparkline(value, [upper]), spooky_hash(str), startswith(str, prefix), strfilter(source, include), substr(str, start, [size]), timezone(tz, ts), trim(str, [chars]), unicode(X), unparse_url(obj), upper(str), xpath(xpath, xmldoc)


parse_url(url)

Parse a URL and return the components in a JSON object. Limitations: not all URL schemes are supported and repeated query parameters are not captured.

Parameters
  • url* — The URL to parse

Examples

To parse the URL ‘https://example.com/search?q=hello%20world’:

;SELECT parse_url('https://example.com/search?q=hello%20world')
{"scheme":"https","username":null,"password":null,"host":"example.com","port":null,"path":"/search","query":"q=hello%20world","parameters":{"q":"hello world"},"fragment":null}

To parse the URL ‘https://alice@[fe80::14ff:4ee5:1215:2fb2]’:

;SELECT parse_url('https://alice@[fe80::14ff:4ee5:1215:2fb2]')
{"scheme":"https","username":"alice","password":null,"host":"[fe80::14ff:4ee5:1215:2fb2]","port":null,"path":"/","query":null,"parameters":null,"fragment":null}
See Also

anonymize(value), char(X), charindex(needle, haystack, [start]), decode(value, algorithm), encode(value, algorithm), endswith(str, suffix), extract(str), group_concat(X, [sep]), group_spooky_hash(str), gunzip(b), gzip(value), humanize_duration(secs), humanize_file_size(value), humanize_id(id), instr(haystack, needle), leftstr(str, N), length(str), logfmt2json(str), lower(str), ltrim(str, [chars]), padc(str, len), padl(str, len), padr(str, len), pretty_print(str), printf(format, X), proper(str), regexp_capture_into_json(string, pattern, [options]), regexp_capture(string, pattern), regexp_match(re, str), regexp_replace(str, re, repl), replace(str, old, replacement), replicate(str, N), reverse(str), rightstr(str, N), rtrim(str, [chars]), sparkline(value, [upper]), spooky_hash(str), startswith(str, prefix), strfilter(source, include), substr(str, start, [size]), timezone(tz, ts), trim(str, [chars]), unicode(X), unparse_url(obj), unparse_url(obj), upper(str), xpath(xpath, xmldoc)


percent_rank()


pi()


power(base, exp)

Returns the base to the given exponent

Parameters
  • base* — The base number

  • exp* — The exponent

Examples

To raise two to the power of three:

;SELECT power(2, 3)
8
See Also

abs(x), acos(num), acosh(num), asin(num), asinh(num), atan2(y, x), atan(num), atanh(num), atn2(y, x), avg(X), ceil(num), degrees(radians), exp(x), floor(num), log10(x), log(x), max(X), min(X), pi(), radians(degrees), round(num, [digits]), sign(num), square(num), sum(X), total(X)


pretty_print(str)

Pretty-print the given string

PRQL Name: text.pretty

Parameters
  • str* — The string to format

Examples

To pretty-print the string ‘{“scheme”: “https”, “host”: “example.com”}’:

;SELECT pretty_print('{"scheme": "https", "host": "example.com"}')
{
    "scheme": "https",
    "host": "example.com"
}
See Also

anonymize(value), char(X), charindex(needle, haystack, [start]), decode(value, algorithm), encode(value, algorithm), endswith(str, suffix), extract(str), group_concat(X, [sep]), group_spooky_hash(str), gunzip(b), gzip(value), humanize_duration(secs), humanize_file_size(value), humanize_id(id), instr(haystack, needle), leftstr(str, N), length(str), logfmt2json(str), lower(str), ltrim(str, [chars]), padc(str, len), padl(str, len), padr(str, len), parse_url(url), printf(format, X), proper(str), regexp_capture_into_json(string, pattern, [options]), regexp_capture(string, pattern), regexp_match(re, str), regexp_replace(str, re, repl), replace(str, old, replacement), replicate(str, N), reverse(str), rightstr(str, N), rtrim(str, [chars]), sparkline(value, [upper]), spooky_hash(str), startswith(str, prefix), strfilter(source, include), substr(str, start, [size]), timezone(tz, ts), trim(str, [chars]), unicode(X), unparse_url(obj), upper(str), xpath(xpath, xmldoc)


printf(format, X)

Returns a string with this functions arguments substituted into the given format. Substitution points are specified using percent (%) options, much like the standard C printf() function.

Parameters
  • format* — The format of the string to return.

  • X* — The argument to substitute at a given position in the format.

Examples

To substitute ‘World’ into the string ‘Hello, %s!’:

;SELECT printf('Hello, %s!', 'World')
Hello, World!

To right-align ‘small’ in the string ‘align:’ with a column width of 10:

;SELECT printf('align: % 10s', 'small')
align:      small

To format 11 with a width of five characters and leading zeroes:

;SELECT printf('value: %05d', 11)
value: 00011
See Also

anonymize(value), char(X), charindex(needle, haystack, [start]), decode(value, algorithm), encode(value, algorithm), endswith(str, suffix), extract(str), group_concat(X, [sep]), group_spooky_hash(str), gunzip(b), gzip(value), humanize_duration(secs), humanize_file_size(value), humanize_id(id), instr(haystack, needle), leftstr(str, N), length(str), logfmt2json(str), lower(str), ltrim(str, [chars]), padc(str, len), padl(str, len), padr(str, len), parse_url(url), pretty_print(str), proper(str), regexp_capture_into_json(string, pattern, [options]), regexp_capture(string, pattern), regexp_match(re, str), regexp_replace(str, re, repl), replace(str, old, replacement), replicate(str, N), reverse(str), rightstr(str, N), rtrim(str, [chars]), sparkline(value, [upper]), spooky_hash(str), startswith(str, prefix), strfilter(source, include), substr(str, start, [size]), timezone(tz, ts), trim(str, [chars]), unicode(X), unparse_url(obj), upper(str), xpath(xpath, xmldoc)


proper(str)

Capitalize the first character of words in the given string

Parameters
  • str* — The string to capitalize.

Examples

To capitalize the words in the string ‘hello, world!’:

;SELECT proper('hello, world!')
Hello, World!
See Also

anonymize(value), char(X), charindex(needle, haystack, [start]), decode(value, algorithm), encode(value, algorithm), endswith(str, suffix), extract(str), group_concat(X, [sep]), group_spooky_hash(str), gunzip(b), gzip(value), humanize_duration(secs), humanize_file_size(value), humanize_id(id), instr(haystack, needle), leftstr(str, N), length(str), logfmt2json(str), lower(str), ltrim(str, [chars]), padc(str, len), padl(str, len), padr(str, len), parse_url(url), pretty_print(str), printf(format, X), regexp_capture_into_json(string, pattern, [options]), regexp_capture(string, pattern), regexp_match(re, str), regexp_replace(str, re, repl), replace(str, old, replacement), replicate(str, N), reverse(str), rightstr(str, N), rtrim(str, [chars]), sparkline(value, [upper]), spooky_hash(str), startswith(str, prefix), strfilter(source, include), substr(str, start, [size]), timezone(tz, ts), trim(str, [chars]), unicode(X), unparse_url(obj), upper(str), xpath(xpath, xmldoc)


quote(X)

Returns the text of an SQL literal which is the value of its argument suitable for inclusion into an SQL statement.

Parameters
  • X* — The string to quote.

Examples

To quote the string ‘abc’:

;SELECT quote('abc')
'abc'

To quote the string ‘abc’123’:

;SELECT quote('abc''123')
'abc''123'

radians(degrees)

Converts degrees to radians

Parameters
  • degrees* — The degrees value to convert to radians

Examples

To convert 180 degrees to radians:

;SELECT radians(180)
3.141592653589793
See Also

abs(x), acos(num), acosh(num), asin(num), asinh(num), atan2(y, x), atan(num), atanh(num), atn2(y, x), avg(X), ceil(num), degrees(radians), exp(x), floor(num), log10(x), log(x), max(X), min(X), pi(), power(base, exp), round(num, [digits]), sign(num), square(num), sum(X), total(X)


raise_error(msg, [reason])

Raises an error with the given message when executed

Parameters
  • msg* — The error message

  • reason — The reason the error occurred

Examples

To raise an error if a variable is not set:

;SELECT ifnull($val, raise_error('please set $val', 'because'))
 error: please set $val
 reason: because
 --> command:1

random()

Returns a pseudo-random integer between -9223372036854775808 and +9223372036854775807.


randomblob(N)

Return an N-byte blob containing pseudo-random bytes.

Parameters
  • N* — The size of the blob in bytes.


rank()


realpath(path)

Returns the resolved version of the given path, expanding symbolic links and resolving ‘.’ and ‘..’ references.

PRQL Name: fs.realpath

Parameters
  • path* — The path to resolve.

See Also

basename(path), dirname(path), joinpath(path), readlink(path)


regexp(re, str)

Test if a string matches a regular expression

Parameters
  • re* — The regular expression to use

  • str* — The string to test against the regular expression


regexp_capture(string, pattern)

A table-valued function that executes a regular-expression over a string and returns the captured values. If the regex only matches a subset of the input string, it will be rerun on the remaining parts of the string until no more matches are found.

Parameters
  • string* — The string to match against the given pattern.

  • pattern* — The regular expression to match.

Examples

To extract the key/value pairs ‘a’/1 and ‘b’/2 from the string ‘a=1; b=2’:

;SELECT * FROM regexp_capture('a=1; b=2', '(\w+)=(\d+)')
match_index capture_index capture_name capture_count range_start range_stop content
          0             0       <NULL>             3           1          4 a=1
          0             1       <NULL>             3           1          2 a
          0             2       <NULL>             3           3          4 1
          1             0       <NULL>             3           6          9 b=2
          1             1       <NULL>             3           6          7 b
          1             2       <NULL>             3           8          9 2
See Also

anonymize(value), char(X), charindex(needle, haystack, [start]), decode(value, algorithm), encode(value, algorithm), endswith(str, suffix), extract(str), group_concat(X, [sep]), group_spooky_hash(str), gunzip(b), gzip(value), humanize_duration(secs), humanize_file_size(value), humanize_id(id), instr(haystack, needle), leftstr(str, N), length(str), logfmt2json(str), lower(str), ltrim(str, [chars]), padc(str, len), padl(str, len), padr(str, len), parse_url(url), pretty_print(str), printf(format, X), proper(str), regexp_capture_into_json(string, pattern, [options]), regexp_match(re, str), regexp_replace(str, re, repl), replace(str, old, replacement), replicate(str, N), reverse(str), rightstr(str, N), rtrim(str, [chars]), sparkline(value, [upper]), spooky_hash(str), startswith(str, prefix), strfilter(source, include), substr(str, start, [size]), timezone(tz, ts), trim(str, [chars]), unicode(X), unparse_url(obj), upper(str), xpath(xpath, xmldoc)


regexp_capture_into_json(string, pattern, [options])

A table-valued function that executes a regular-expression over a string and returns the captured values as a JSON object. If the regex only matches a subset of the input string, it will be rerun on the remaining parts of the string until no more matches are found.

Parameters
  • string* — The string to match against the given pattern.

  • pattern* — The regular expression to match.

  • options — A JSON object with the following option: convert-numbers - True (default) if text that looks like numeric data should be converted to JSON numbers, false if they should be captured as strings.

Examples

To extract the key/value pairs ‘a’/1 and ‘b’/2 from the string ‘a=1; b=2’:

;SELECT * FROM regexp_capture_into_json('a=1; b=2', '(\w+)=(\d+)')
match_index     content
          0 {"col_0⋯l_1":1}
          1 {"col_0⋯l_1":2}
See Also

anonymize(value), char(X), charindex(needle, haystack, [start]), decode(value, algorithm), encode(value, algorithm), endswith(str, suffix), extract(str), group_concat(X, [sep]), group_spooky_hash(str), gunzip(b), gzip(value), humanize_duration(secs), humanize_file_size(value), humanize_id(id), instr(haystack, needle), leftstr(str, N), length(str), logfmt2json(str), lower(str), ltrim(str, [chars]), padc(str, len), padl(str, len), padr(str, len), parse_url(url), pretty_print(str), printf(format, X), proper(str), regexp_capture(string, pattern), regexp_match(re, str), regexp_replace(str, re, repl), replace(str, old, replacement), replicate(str, N), reverse(str), rightstr(str, N), rtrim(str, [chars]), sparkline(value, [upper]), spooky_hash(str), startswith(str, prefix), strfilter(source, include), substr(str, start, [size]), timezone(tz, ts), trim(str, [chars]), unicode(X), unparse_url(obj), upper(str), xpath(xpath, xmldoc)


regexp_match(re, str)

Match a string against a regular expression and return the capture groups as JSON.

PRQL Name: text.regexp_match

Parameters
  • re* — The regular expression to use

  • str* — The string to test against the regular expression

Examples

To capture the digits from the string ‘123’:

;SELECT regexp_match('(\d+)', '123')
123

To capture a number and word into a JSON object with the properties ‘col_0’ and ‘col_1’:

;SELECT regexp_match('(\d+) (\w+)', '123 four')
{"col_0":123,"col_1":"four"}

To capture a number and word into a JSON object with the named properties ‘num’ and ‘str’:

;SELECT regexp_match('(?<num>\d+) (?<str>\w+)', '123 four')
{"num":123,"str":"four"}
See Also

anonymize(value), char(X), charindex(needle, haystack, [start]), decode(value, algorithm), encode(value, algorithm), endswith(str, suffix), extract(str), group_concat(X, [sep]), group_spooky_hash(str), gunzip(b), gzip(value), humanize_duration(secs), humanize_file_size(value), humanize_id(id), instr(haystack, needle), leftstr(str, N), length(str), logfmt2json(str), lower(str), ltrim(str, [chars]), padc(str, len), padl(str, len), padr(str, len), parse_url(url), pretty_print(str), printf(format, X), proper(str), regexp_capture_into_json(string, pattern, [options]), regexp_capture(string, pattern), regexp_replace(str, re, repl), regexp_replace(str, re, repl), replace(str, old, replacement), replicate(str, N), reverse(str), rightstr(str, N), rtrim(str, [chars]), sparkline(value, [upper]), spooky_hash(str), startswith(str, prefix), strfilter(source, include), substr(str, start, [size]), timezone(tz, ts), trim(str, [chars]), unicode(X), unparse_url(obj), upper(str), xpath(xpath, xmldoc)


regexp_replace(str, re, repl)

Replace the parts of a string that match a regular expression.

PRQL Name: text.regexp_replace

Parameters
  • str* — The string to perform replacements on

  • re* — The regular expression to match

  • repl* — The replacement string. You can reference capture groups with a backslash followed by the number of the group, starting with 1.

Examples

To replace the word at the start of the string ‘Hello, World!’ with ‘Goodbye’:

;SELECT regexp_replace('Hello, World!', '^(\w+)', 'Goodbye')
Goodbye, World!

To wrap alphanumeric words with angle brackets:

;SELECT regexp_replace('123 abc', '(\w+)', '<\1>')
<123> <abc>
See Also

anonymize(value), char(X), charindex(needle, haystack, [start]), decode(value, algorithm), encode(value, algorithm), endswith(str, suffix), extract(str), group_concat(X, [sep]), group_spooky_hash(str), gunzip(b), gzip(value), humanize_duration(secs), humanize_file_size(value), humanize_id(id), instr(haystack, needle), leftstr(str, N), length(str), logfmt2json(str), lower(str), ltrim(str, [chars]), padc(str, len), padl(str, len), padr(str, len), parse_url(url), pretty_print(str), printf(format, X), proper(str), regexp_capture_into_json(string, pattern, [options]), regexp_capture(string, pattern), regexp_match(re, str), regexp_match(re, str), replace(str, old, replacement), replicate(str, N), reverse(str), rightstr(str, N), rtrim(str, [chars]), sparkline(value, [upper]), spooky_hash(str), startswith(str, prefix), strfilter(source, include), substr(str, start, [size]), timezone(tz, ts), trim(str, [chars]), unicode(X), unparse_url(obj), upper(str), xpath(xpath, xmldoc)


replace(str, old, replacement)

Returns a string formed by substituting the replacement string for every occurrence of the old string in the given string.

Parameters
  • str* — The string to perform substitutions on.

  • old* — The string to be replaced.

  • replacement* — The string to replace any occurrences of the old string with.

Examples

To replace the string ‘x’ with ‘z’ in ‘abc’:

;SELECT replace('abc', 'x', 'z')
abc

To replace the string ‘a’ with ‘z’ in ‘abc’:

;SELECT replace('abc', 'a', 'z')
zbc
See Also

anonymize(value), char(X), charindex(needle, haystack, [start]), decode(value, algorithm), encode(value, algorithm), endswith(str, suffix), extract(str), group_concat(X, [sep]), group_spooky_hash(str), gunzip(b), gzip(value), humanize_duration(secs), humanize_file_size(value), humanize_id(id), instr(haystack, needle), leftstr(str, N), length(str), logfmt2json(str), lower(str), ltrim(str, [chars]), padc(str, len), padl(str, len), padr(str, len), parse_url(url), pretty_print(str), printf(format, X), proper(str), regexp_capture_into_json(string, pattern, [options]), regexp_capture(string, pattern), regexp_match(re, str), regexp_replace(str, re, repl), replicate(str, N), reverse(str), rightstr(str, N), rtrim(str, [chars]), sparkline(value, [upper]), spooky_hash(str), startswith(str, prefix), strfilter(source, include), substr(str, start, [size]), timezone(tz, ts), trim(str, [chars]), unicode(X), unparse_url(obj), upper(str), xpath(xpath, xmldoc)


replicate(str, N)

Returns the given string concatenated N times.

Parameters
  • str* — The string to replicate.

  • N* — The number of times to replicate the string.

Examples

To repeat the string ‘abc’ three times:

;SELECT replicate('abc', 3)
abcabcabc
See Also

anonymize(value), char(X), charindex(needle, haystack, [start]), decode(value, algorithm), encode(value, algorithm), endswith(str, suffix), extract(str), group_concat(X, [sep]), group_spooky_hash(str), gunzip(b), gzip(value), humanize_duration(secs), humanize_file_size(value), humanize_id(id), instr(haystack, needle), leftstr(str, N), length(str), logfmt2json(str), lower(str), ltrim(str, [chars]), padc(str, len), padl(str, len), padr(str, len), parse_url(url), pretty_print(str), printf(format, X), proper(str), regexp_capture_into_json(string, pattern, [options]), regexp_capture(string, pattern), regexp_match(re, str), regexp_replace(str, re, repl), replace(str, old, replacement), reverse(str), rightstr(str, N), rtrim(str, [chars]), sparkline(value, [upper]), spooky_hash(str), startswith(str, prefix), strfilter(source, include), substr(str, start, [size]), timezone(tz, ts), trim(str, [chars]), unicode(X), unparse_url(obj), upper(str), xpath(xpath, xmldoc)


reverse(str)

Returns the reverse of the given string.

PRQL Name: text.reverse

Parameters
  • str* — The string to reverse.

Examples

To reverse the string ‘abc’:

;SELECT reverse('abc')
cba
See Also

anonymize(value), char(X), charindex(needle, haystack, [start]), decode(value, algorithm), encode(value, algorithm), endswith(str, suffix), extract(str), group_concat(X, [sep]), group_spooky_hash(str), gunzip(b), gzip(value), humanize_duration(secs), humanize_file_size(value), humanize_id(id), instr(haystack, needle), leftstr(str, N), length(str), logfmt2json(str), lower(str), ltrim(str, [chars]), padc(str, len), padl(str, len), padr(str, len), parse_url(url), pretty_print(str), printf(format, X), proper(str), regexp_capture_into_json(string, pattern, [options]), regexp_capture(string, pattern), regexp_match(re, str), regexp_replace(str, re, repl), replace(str, old, replacement), replicate(str, N), rightstr(str, N), rtrim(str, [chars]), sparkline(value, [upper]), spooky_hash(str), startswith(str, prefix), strfilter(source, include), substr(str, start, [size]), timezone(tz, ts), trim(str, [chars]), unicode(X), unparse_url(obj), upper(str), xpath(xpath, xmldoc)


rightstr(str, N)

Returns the N rightmost (UTF-8) characters in the given string.

Parameters
  • str* — The string to return subset.

  • N* — The number of characters from the right side of the string to return.

Examples

To get the last character of the string ‘abc’:

;SELECT rightstr('abc', 1)
c

To get the last ten characters of a string, regardless of size:

;SELECT rightstr('abc', 10)
abc
See Also

anonymize(value), char(X), charindex(needle, haystack, [start]), decode(value, algorithm), encode(value, algorithm), endswith(str, suffix), extract(str), group_concat(X, [sep]), group_spooky_hash(str), gunzip(b), gzip(value), humanize_duration(secs), humanize_file_size(value), humanize_id(id), instr(haystack, needle), leftstr(str, N), length(str), logfmt2json(str), lower(str), ltrim(str, [chars]), padc(str, len), padl(str, len), padr(str, len), parse_url(url), pretty_print(str), printf(format, X), proper(str), regexp_capture_into_json(string, pattern, [options]), regexp_capture(string, pattern), regexp_match(re, str), regexp_replace(str, re, repl), replace(str, old, replacement), replicate(str, N), reverse(str), rtrim(str, [chars]), sparkline(value, [upper]), spooky_hash(str), startswith(str, prefix), strfilter(source, include), substr(str, start, [size]), timezone(tz, ts), trim(str, [chars]), unicode(X), unparse_url(obj), upper(str), xpath(xpath, xmldoc)


round(num, [digits])

Returns a floating-point value rounded to the given number of digits to the right of the decimal point.

Parameters
  • num* — The value to round.

  • digits — The number of digits to the right of the decimal to round to.

Examples

To round the number 123.456 to an integer:

;SELECT round(123.456)
123

To round the number 123.456 to a precision of 1:

;SELECT round(123.456, 1)
123.5

To round the number 123.456 to a precision of 5:

;SELECT round(123.456, 5)
123.456
See Also

abs(x), acos(num), acosh(num), asin(num), asinh(num), atan2(y, x), atan(num), atanh(num), atn2(y, x), avg(X), ceil(num), degrees(radians), exp(x), floor(num), log10(x), log(x), max(X), min(X), pi(), power(base, exp), radians(degrees), sign(num), square(num), sum(X), total(X)


row_number()

Returns the number of the row within the current partition, starting from 1.

Examples

To number messages from a process:

;SELECT row_number() OVER (PARTITION BY ex_procname ORDER BY log_line) AS msg_num, ex_procname, log_body FROM lnav_example_log
 msg_num   ex_procname    log_body
         1 gw          Goodbye, World!
         2 gw          Goodbye, World!
         3 gw          Goodbye, World!
         1 hw          Hello, World!
See Also

cume_dist(), dense_rank(), first_value(expr), lag(expr, [offset], [default]), last_value(expr), lead(expr, [offset], [default]), nth_value(expr, N), ntile(groups), percent_rank(), rank()


rtrim(str, [chars])

Returns a string formed by removing any and all characters that appear in the second argument from the right side of the first.

Parameters
  • str* — The string to trim characters from the right side

  • chars — The characters to trim. Defaults to spaces.

Examples

To trim the space characters from the end of the string ‘abc ‘:

;SELECT rtrim('abc   ')
abc

To trim the characters ‘b’ and ‘c’ from the string ‘abbbbcccc’:

;SELECT rtrim('abbbbcccc', 'bc')
a
See Also

anonymize(value), char(X), charindex(needle, haystack, [start]), decode(value, algorithm), encode(value, algorithm), endswith(str, suffix), extract(str), group_concat(X, [sep]), group_spooky_hash(str), gunzip(b), gzip(value), humanize_duration(secs), humanize_file_size(value), humanize_id(id), instr(haystack, needle), leftstr(str, N), length(str), logfmt2json(str), lower(str), ltrim(str, [chars]), padc(str, len), padl(str, len), padr(str, len), parse_url(url), pretty_print(str), printf(format, X), proper(str), regexp_capture_into_json(string, pattern, [options]), regexp_capture(string, pattern), regexp_match(re, str), regexp_replace(str, re, repl), replace(str, old, replacement), replicate(str, N), reverse(str), rightstr(str, N), sparkline(value, [upper]), spooky_hash(str), startswith(str, prefix), strfilter(source, include), substr(str, start, [size]), timezone(tz, ts), trim(str, [chars]), unicode(X), unparse_url(obj), upper(str), xpath(xpath, xmldoc)


shell_exec(cmd, [input], [options])

Executes a shell command and returns its output.

PRQL Name: shell.exec

Parameters
  • cmd* — The command to execute.

  • input — A blob of data to write to the command’s standard input.

  • options — A JSON object containing options for the execution with the following properties:

    • env — An object containing the environment variables to set or, if NULL, to unset.

See Also


sign(num)

Returns the sign of the given number as -1, 0, or 1

Parameters
  • num* — The number

Examples

To get the sign of 10:

;SELECT sign(10)
1

To get the sign of 0:

;SELECT sign(0)
0

To get the sign of -10:

;SELECT sign(-10)
-1
See Also

abs(x), acos(num), acosh(num), asin(num), asinh(num), atan2(y, x), atan(num), atanh(num), atn2(y, x), avg(X), ceil(num), degrees(radians), exp(x), floor(num), log10(x), log(x), max(X), min(X), pi(), power(base, exp), radians(degrees), round(num, [digits]), square(num), sum(X), total(X)


sparkline(value, [upper])

Function used to generate a sparkline bar chart. The non-aggregate version converts a single numeric value on a range to a bar chart character. The aggregate version returns a string with a bar character for every numeric input

PRQL Name: text.sparkline

Parameters
  • value* — The numeric value to convert

  • upper — The upper bound of the numeric range. The non-aggregate version defaults to 100. The aggregate version uses the largest value in the inputs.

Examples

To get the unicode block element for the value 32 in the range of 0-128:

;SELECT sparkline(32, 128)

To chart the values in a JSON array:

;SELECT sparkline(value) FROM json_each('[0, 1, 2, 3, 4, 5, 6, 7, 8]')
 ▁▂▃▄▅▆▇█
See Also

anonymize(value), char(X), charindex(needle, haystack, [start]), decode(value, algorithm), encode(value, algorithm), endswith(str, suffix), extract(str), group_concat(X, [sep]), group_spooky_hash(str), gunzip(b), gzip(value), humanize_duration(secs), humanize_file_size(value), humanize_id(id), instr(haystack, needle), leftstr(str, N), length(str), logfmt2json(str), lower(str), ltrim(str, [chars]), padc(str, len), padl(str, len), padr(str, len), parse_url(url), pretty_print(str), printf(format, X), proper(str), regexp_capture_into_json(string, pattern, [options]), regexp_capture(string, pattern), regexp_match(re, str), regexp_replace(str, re, repl), replace(str, old, replacement), replicate(str, N), reverse(str), rightstr(str, N), rtrim(str, [chars]), spooky_hash(str), startswith(str, prefix), strfilter(source, include), substr(str, start, [size]), timezone(tz, ts), trim(str, [chars]), unicode(X), unparse_url(obj), upper(str), xpath(xpath, xmldoc)


spooky_hash(str)

Compute the hash value for the given arguments.

Parameters
  • str — The string to hash

Examples

To produce a hash for the string ‘Hello, World!’:

;SELECT spooky_hash('Hello, World!')
0b1d52cc5427db4c6a9eed9d3e5700f4

To produce a hash for the parameters where one is NULL:

;SELECT spooky_hash('Hello, World!', NULL)
c96ee75d48e6ea444fee8af948f6da25

To produce a hash for the parameters where one is an empty string:

;SELECT spooky_hash('Hello, World!', '')
c96ee75d48e6ea444fee8af948f6da25

To produce a hash for the parameters where one is a number:

;SELECT spooky_hash('Hello, World!', 123)
f96b3d9c1a19f4394c97a1b79b1880df
See Also

anonymize(value), char(X), charindex(needle, haystack, [start]), decode(value, algorithm), encode(value, algorithm), endswith(str, suffix), extract(str), group_concat(X, [sep]), group_spooky_hash(str), gunzip(b), gzip(value), humanize_duration(secs), humanize_file_size(value), humanize_id(id), instr(haystack, needle), leftstr(str, N), length(str), logfmt2json(str), lower(str), ltrim(str, [chars]), padc(str, len), padl(str, len), padr(str, len), parse_url(url), pretty_print(str), printf(format, X), proper(str), regexp_capture_into_json(string, pattern, [options]), regexp_capture(string, pattern), regexp_match(re, str), regexp_replace(str, re, repl), replace(str, old, replacement), replicate(str, N), reverse(str), rightstr(str, N), rtrim(str, [chars]), sparkline(value, [upper]), startswith(str, prefix), strfilter(source, include), substr(str, start, [size]), timezone(tz, ts), trim(str, [chars]), unicode(X), unparse_url(obj), upper(str), xpath(xpath, xmldoc)


sqlite_compileoption_get(N)

Returns the N-th compile-time option used to build SQLite or NULL if N is out of range.

Parameters
  • N* — The option number to get


sqlite_compileoption_used(option)

Returns true (1) or false (0) depending on whether or not that compile-time option was used during the build.

Parameters
  • option* — The name of the compile-time option.

Examples

To check if the SQLite library was compiled with ENABLE_FTS3:

;SELECT sqlite_compileoption_used('ENABLE_FTS3')
1

sqlite_source_id()

Returns a string that identifies the specific version of the source code that was used to build the SQLite library.


sqlite_version()

Returns the version string for the SQLite library that is running.


square(num)

Returns the square of the argument

Parameters
  • num* — The number to square

Examples

To get the square of two:

;SELECT square(2)
4
See Also

abs(x), acos(num), acosh(num), asin(num), asinh(num), atan2(y, x), atan(num), atanh(num), atn2(y, x), avg(X), ceil(num), degrees(radians), exp(x), floor(num), log10(x), log(x), max(X), min(X), pi(), power(base, exp), radians(degrees), round(num, [digits]), sign(num), sum(X), total(X)


startswith(str, prefix)

Test if a string begins with the given prefix

Parameters
  • str* — The string to test

  • prefix* — The prefix to check in the string

Examples

To test if the string ‘foobar’ starts with ‘foo’:

;SELECT startswith('foobar', 'foo')
1

To test if the string ‘foobar’ starts with ‘bar’:

;SELECT startswith('foobar', 'bar')
0
See Also

anonymize(value), char(X), charindex(needle, haystack, [start]), decode(value, algorithm), encode(value, algorithm), endswith(str, suffix), extract(str), group_concat(X, [sep]), group_spooky_hash(str), gunzip(b), gzip(value), humanize_duration(secs), humanize_file_size(value), humanize_id(id), instr(haystack, needle), leftstr(str, N), length(str), logfmt2json(str), lower(str), ltrim(str, [chars]), padc(str, len), padl(str, len), padr(str, len), parse_url(url), pretty_print(str), printf(format, X), proper(str), regexp_capture_into_json(string, pattern, [options]), regexp_capture(string, pattern), regexp_match(re, str), regexp_replace(str, re, repl), replace(str, old, replacement), replicate(str, N), reverse(str), rightstr(str, N), rtrim(str, [chars]), sparkline(value, [upper]), spooky_hash(str), strfilter(source, include), substr(str, start, [size]), timezone(tz, ts), trim(str, [chars]), unicode(X), unparse_url(obj), upper(str), xpath(xpath, xmldoc)


strfilter(source, include)

Returns the source string with only the characters given in the second parameter

Parameters
  • source* — The string to filter

  • include* — The characters to include in the result

Examples

To get the ‘b’, ‘c’, and ‘d’ characters from the string ‘abcabc’:

;SELECT strfilter('abcabc', 'bcd')
bcbc
See Also

anonymize(value), char(X), charindex(needle, haystack, [start]), decode(value, algorithm), encode(value, algorithm), endswith(str, suffix), extract(str), group_concat(X, [sep]), group_spooky_hash(str), gunzip(b), gzip(value), humanize_duration(secs), humanize_file_size(value), humanize_id(id), instr(haystack, needle), leftstr(str, N), length(str), logfmt2json(str), lower(str), ltrim(str, [chars]), padc(str, len), padl(str, len), padr(str, len), parse_url(url), pretty_print(str), printf(format, X), proper(str), regexp_capture_into_json(string, pattern, [options]), regexp_capture(string, pattern), regexp_match(re, str), regexp_replace(str, re, repl), replace(str, old, replacement), replicate(str, N), reverse(str), rightstr(str, N), rtrim(str, [chars]), sparkline(value, [upper]), spooky_hash(str), startswith(str, prefix), substr(str, start, [size]), timezone(tz, ts), trim(str, [chars]), unicode(X), unparse_url(obj), upper(str), xpath(xpath, xmldoc)


strftime(format, timestring, modifier)

Returns the date formatted according to the format string specified as the first argument.

Parameters
  • format* — A format string with substitutions similar to those found in the strftime() standard C library.

  • timestring* — The string to convert to a date with time.

  • modifier — A transformation that is applied to the value to the left.

Examples

To get the year from the timestamp ‘2017-01-02T03:04:05’:

;SELECT strftime('%Y', '2017-01-02T03:04:05')
2017

To create a string with the time from the timestamp ‘2017-01-02T03:04:05’ plus one minute:

;SELECT strftime('The time is: %H:%M:%S', '2017-01-02T03:04:05', '+1 minute')
The time is: 03:05:05

To create a string with the Julian day from the epoch timestamp 1491341842:

;SELECT strftime('Julian day: %J', 1491341842, 'unixepoch')
Julian day: 2457848.400949074
See Also

date(timestring, modifier), datetime(timestring, modifier), humanize_duration(secs), julianday(timestring, modifier), time(timestring, modifier), timediff(time1, time2), timeslice(time, slice), timezone(tz, ts)


substr(str, start, [size])

Returns a substring of input string X that begins with the Y-th character and which is Z characters long.

Parameters
  • str* — The string to extract a substring from.

  • start* — The index within ‘str’ that is the start of the substring. Indexes begin at 1. A negative value means that the substring is found by counting from the right rather than the left.

  • size — The size of the substring. If not given, then all characters through the end of the string are returned. If the value is negative, then the characters before the start are returned.

Examples

To get the substring starting at the second character until the end of the string ‘abc’:

;SELECT substr('abc', 2)
bc

To get the substring of size one starting at the second character of the string ‘abc’:

;SELECT substr('abc', 2, 1)
b

To get the substring starting at the last character until the end of the string ‘abc’:

;SELECT substr('abc', -1)
c

To get the substring starting at the last character and going backwards one step of the string ‘abc’:

;SELECT substr('abc', -1, -1)
b
See Also

anonymize(value), char(X), charindex(needle, haystack, [start]), decode(value, algorithm), encode(value, algorithm), endswith(str, suffix), extract(str), group_concat(X, [sep]), group_spooky_hash(str), gunzip(b), gzip(value), humanize_duration(secs), humanize_file_size(value), humanize_id(id), instr(haystack, needle), leftstr(str, N), length(str), logfmt2json(str), lower(str), ltrim(str, [chars]), padc(str, len), padl(str, len), padr(str, len), parse_url(url), pretty_print(str), printf(format, X), proper(str), regexp_capture_into_json(string, pattern, [options]), regexp_capture(string, pattern), regexp_match(re, str), regexp_replace(str, re, repl), replace(str, old, replacement), replicate(str, N), reverse(str), rightstr(str, N), rtrim(str, [chars]), sparkline(value, [upper]), spooky_hash(str), startswith(str, prefix), strfilter(source, include), timezone(tz, ts), trim(str, [chars]), unicode(X), unparse_url(obj), upper(str), xpath(xpath, xmldoc)


sum(X)

Returns the sum of the values in the group as an integer.

Parameters
  • X* — The values to add.

Examples

To sum all of the values in the column ‘ex_duration’ from the table ‘lnav_example_log’:

;SELECT sum(ex_duration) FROM lnav_example_log
17
See Also

abs(x), acos(num), acosh(num), asin(num), asinh(num), atan2(y, x), atan(num), atanh(num), atn2(y, x), avg(X), ceil(num), degrees(radians), exp(x), floor(num), log10(x), log(x), max(X), min(X), pi(), power(base, exp), radians(degrees), round(num, [digits]), sign(num), square(num), total(X)


time(timestring, modifier)

Returns the time in this format: HH:MM:SS.

Parameters
  • timestring* — The string to convert to a time.

  • modifier — A transformation that is applied to the value to the left.

Examples

To get the time portion of the timestamp ‘2017-01-02T03:04:05’:

;SELECT time('2017-01-02T03:04:05')
03:04:05

To get the time portion of the timestamp ‘2017-01-02T03:04:05’ plus one minute:

;SELECT time('2017-01-02T03:04:05', '+1 minute')
03:05:05

To get the time portion of the epoch timestamp 1491341842:

;SELECT time(1491341842, 'unixepoch')
21:37:22
See Also

date(timestring, modifier), datetime(timestring, modifier), humanize_duration(secs), julianday(timestring, modifier), strftime(format, timestring, modifier), timediff(time1, time2), timeslice(time, slice), timezone(tz, ts)


timediff(time1, time2)

Compute the difference between two timestamps in seconds

PRQL Name: time.diff

Parameters
  • time1* — The first timestamp

  • time2* — The timestamp to subtract from the first

Examples

To get the difference between two timestamps:

;SELECT timediff('2017-02-03T04:05:06', '2017-02-03T04:05:00')
6

To get the difference between relative timestamps:

;SELECT timediff('today', 'yesterday')
86400
See Also

date(timestring, modifier), datetime(timestring, modifier), humanize_duration(secs), julianday(timestring, modifier), strftime(format, timestring, modifier), time(timestring, modifier), timeslice(time, slice), timezone(tz, ts)


timeslice(time, slice)

Return the start of the slice of time that the given timestamp falls in. If the time falls outside of the slice, NULL is returned.

PRQL Name: time.slice

Parameters
  • time* — The timestamp to get the time slice for.

  • slice* — The size of the time slices

Examples

To get the timestamp rounded down to the start of the ten minute slice:

;SELECT timeslice('2017-01-01T05:05:00', '10m')
2017-01-01 05:00:00.000

To group log messages into five minute buckets and count them:

;SELECT timeslice(log_time_msecs, '5m') AS slice, count(1)
FROM lnav_example_log GROUP BY slice

slice count(1)

2017-02⋯:00.000 2 2017-02⋯:00.000 1 2017-02⋯:00.000 1

To group log messages by those before 4:30am and after:

;SELECT timeslice(log_time_msecs, 'before 4:30am') AS slice, count(1) FROM lnav_example_log GROUP BY slice
     slice       count(1)
<NULL>                   1
2017-02:00.000          3
See Also

date(timestring, modifier), datetime(timestring, modifier), humanize_duration(secs), julianday(timestring, modifier), strftime(format, timestring, modifier), time(timestring, modifier), timediff(time1, time2), timezone(tz, ts)


timezone(tz, ts)

Convert a timestamp to the given timezone

PRQL Name: time.to_zone

Parameters
  • tz* — The target timezone

  • ts* — The source timestamp

Examples

To convert a time to America/Los_Angeles:

;SELECT timezone('America/Los_Angeles', '2022-03-02T10:00')
2022-03-02T02:00:00.000000-0800
See Also

anonymize(value), char(X), charindex(needle, haystack, [start]), date(timestring, modifier), datetime(timestring, modifier), decode(value, algorithm), encode(value, algorithm), endswith(str, suffix), extract(str), group_concat(X, [sep]), group_spooky_hash(str), gunzip(b), gzip(value), humanize_duration(secs), humanize_duration(secs), humanize_file_size(value), humanize_id(id), instr(haystack, needle), julianday(timestring, modifier), leftstr(str, N), length(str), logfmt2json(str), lower(str), ltrim(str, [chars]), padc(str, len), padl(str, len), padr(str, len), parse_url(url), pretty_print(str), printf(format, X), proper(str), regexp_capture_into_json(string, pattern, [options]), regexp_capture(string, pattern), regexp_match(re, str), regexp_replace(str, re, repl), replace(str, old, replacement), replicate(str, N), reverse(str), rightstr(str, N), rtrim(str, [chars]), sparkline(value, [upper]), spooky_hash(str), startswith(str, prefix), strfilter(source, include), strftime(format, timestring, modifier), substr(str, start, [size]), time(timestring, modifier), timediff(time1, time2), timeslice(time, slice), trim(str, [chars]), unicode(X), unparse_url(obj), upper(str), xpath(xpath, xmldoc)


total(X)

Returns the sum of the values in the group as a floating-point.

Parameters
  • X* — The values to add.

Examples

To total all of the values in the column ‘ex_duration’ from the table ‘lnav_example_log’:

;SELECT total(ex_duration) FROM lnav_example_log
17
See Also

abs(x), acos(num), acosh(num), asin(num), asinh(num), atan2(y, x), atan(num), atanh(num), atn2(y, x), avg(X), ceil(num), degrees(radians), exp(x), floor(num), log10(x), log(x), max(X), min(X), pi(), power(base, exp), radians(degrees), round(num, [digits]), sign(num), square(num), sum(X)


total_changes()

Returns the number of row changes caused by INSERT, UPDATE or DELETE statements since the current database connection was opened.


trim(str, [chars])

Returns a string formed by removing any and all characters that appear in the second argument from the left and right sides of the first.

Parameters
  • str* — The string to trim characters from the left and right sides.

  • chars — The characters to trim. Defaults to spaces.

Examples

To trim spaces from the start and end of the string ‘ abc ‘:

;SELECT trim('    abc   ')
abc

To trim the characters ‘-’ and ‘+’ from the string ‘-+abc+-‘:

;SELECT trim('-+abc+-', '-+')
abc
See Also

anonymize(value), char(X), charindex(needle, haystack, [start]), decode(value, algorithm), encode(value, algorithm), endswith(str, suffix), extract(str), group_concat(X, [sep]), group_spooky_hash(str), gunzip(b), gzip(value), humanize_duration(secs), humanize_file_size(value), humanize_id(id), instr(haystack, needle), leftstr(str, N), length(str), logfmt2json(str), lower(str), ltrim(str, [chars]), padc(str, len), padl(str, len), padr(str, len), parse_url(url), pretty_print(str), printf(format, X), proper(str), regexp_capture_into_json(string, pattern, [options]), regexp_capture(string, pattern), regexp_match(re, str), regexp_replace(str, re, repl), replace(str, old, replacement), replicate(str, N), reverse(str), rightstr(str, N), rtrim(str, [chars]), sparkline(value, [upper]), spooky_hash(str), startswith(str, prefix), strfilter(source, include), substr(str, start, [size]), timezone(tz, ts), unicode(X), unparse_url(obj), upper(str), xpath(xpath, xmldoc)


typeof(X)

Returns a string that indicates the datatype of the expression X: “null”, “integer”, “real”, “text”, or “blob”.

Parameters
  • X* — The expression to check.

Examples

To get the type of the number 1:

;SELECT typeof(1)
integer

To get the type of the string ‘abc’:

;SELECT typeof('abc')
text

unicode(X)

Returns the numeric unicode code point corresponding to the first character of the string X.

Parameters
  • X* — The string to examine.

Examples

To get the unicode code point for the first character of ‘abc’:

;SELECT unicode('abc')
97
See Also

anonymize(value), char(X), charindex(needle, haystack, [start]), decode(value, algorithm), encode(value, algorithm), endswith(str, suffix), extract(str), group_concat(X, [sep]), group_spooky_hash(str), gunzip(b), gzip(value), humanize_duration(secs), humanize_file_size(value), humanize_id(id), instr(haystack, needle), leftstr(str, N), length(str), logfmt2json(str), lower(str), ltrim(str, [chars]), padc(str, len), padl(str, len), padr(str, len), parse_url(url), pretty_print(str), printf(format, X), proper(str), regexp_capture_into_json(string, pattern, [options]), regexp_capture(string, pattern), regexp_match(re, str), regexp_replace(str, re, repl), replace(str, old, replacement), replicate(str, N), reverse(str), rightstr(str, N), rtrim(str, [chars]), sparkline(value, [upper]), spooky_hash(str), startswith(str, prefix), strfilter(source, include), substr(str, start, [size]), timezone(tz, ts), trim(str, [chars]), unparse_url(obj), upper(str), xpath(xpath, xmldoc)


unlikely(value)

Short-hand for likelihood(X, 0.0625)

Parameters
  • value* — The boolean value to return


unparse_url(obj)

Convert a JSON object containing the parts of a URL into a URL string

Parameters
  • obj* — The JSON object containing the URL parts

Examples

To unparse the object ‘{“scheme”: “https”, “host”: “example.com”}’:

;SELECT unparse_url('{"scheme": "https", "host": "example.com"}')
https://example.com/
See Also

anonymize(value), char(X), charindex(needle, haystack, [start]), decode(value, algorithm), encode(value, algorithm), endswith(str, suffix), extract(str), group_concat(X, [sep]), group_spooky_hash(str), gunzip(b), gzip(value), humanize_duration(secs), humanize_file_size(value), humanize_id(id), instr(haystack, needle), leftstr(str, N), length(str), logfmt2json(str), lower(str), ltrim(str, [chars]), padc(str, len), padl(str, len), padr(str, len), parse_url(url), parse_url(url), pretty_print(str), printf(format, X), proper(str), regexp_capture_into_json(string, pattern, [options]), regexp_capture(string, pattern), regexp_match(re, str), regexp_replace(str, re, repl), replace(str, old, replacement), replicate(str, N), reverse(str), rightstr(str, N), rtrim(str, [chars]), sparkline(value, [upper]), spooky_hash(str), startswith(str, prefix), strfilter(source, include), substr(str, start, [size]), timezone(tz, ts), trim(str, [chars]), unicode(X), upper(str), xpath(xpath, xmldoc)


upper(str)

Returns a copy of the given string with all ASCII characters converted to upper case.

Parameters
  • str* — The string to convert.

Examples

To uppercase the string ‘aBc’:

;SELECT upper('aBc')
ABC
See Also

anonymize(value), char(X), charindex(needle, haystack, [start]), decode(value, algorithm), encode(value, algorithm), endswith(str, suffix), extract(str), group_concat(X, [sep]), group_spooky_hash(str), gunzip(b), gzip(value), humanize_duration(secs), humanize_file_size(value), humanize_id(id), instr(haystack, needle), leftstr(str, N), length(str), logfmt2json(str), lower(str), ltrim(str, [chars]), padc(str, len), padl(str, len), padr(str, len), parse_url(url), pretty_print(str), printf(format, X), proper(str), regexp_capture_into_json(string, pattern, [options]), regexp_capture(string, pattern), regexp_match(re, str), regexp_replace(str, re, repl), replace(str, old, replacement), replicate(str, N), reverse(str), rightstr(str, N), rtrim(str, [chars]), sparkline(value, [upper]), spooky_hash(str), startswith(str, prefix), strfilter(source, include), substr(str, start, [size]), timezone(tz, ts), trim(str, [chars]), unicode(X), unparse_url(obj), xpath(xpath, xmldoc)


xpath(xpath, xmldoc)

A table-valued function that executes an xpath expression over an XML string and returns the selected values.

Parameters
  • xpath* — The XPATH expression to evaluate over the XML document.

  • xmldoc* — The XML document as a string.

Examples

To select the XML nodes on the path ‘/abc/def’:

;SELECT * FROM xpath('/abc/def', '<abc><def a="b">Hello</def><def>Bye</def></abc>')
    result       node_path  node_attr node_text
<def a=</def> /abc/def[1] {"a":"b"} Hello
<def>Bye</def> /abc/def[2] {}        Bye

To select all ‘a’ attributes on the path ‘/abc/def’:

;SELECT * FROM xpath('/abc/def/@a', '<abc><def a="b">Hello</def><def>Bye</def></abc>')
result   node_path    node_attr node_text
b      /abc/def[1]/@a {"a":"b"} Hello

To select the text nodes on the path ‘/abc/def’:

;SELECT * FROM xpath('/abc/def/text()', '<abc><def a="b">Hello &#x2605;</def></abc>')
result     node_path    node_attr node_text
Hello  /abc/def/text() {}        Hello 
See Also

anonymize(value), char(X), charindex(needle, haystack, [start]), decode(value, algorithm), encode(value, algorithm), endswith(str, suffix), extract(str), group_concat(X, [sep]), group_spooky_hash(str), gunzip(b), gzip(value), humanize_duration(secs), humanize_file_size(value), humanize_id(id), instr(haystack, needle), leftstr(str, N), length(str), logfmt2json(str), lower(str), ltrim(str, [chars]), padc(str, len), padl(str, len), padr(str, len), parse_url(url), pretty_print(str), printf(format, X), proper(str), regexp_capture_into_json(string, pattern, [options]), regexp_capture(string, pattern), regexp_match(re, str), regexp_replace(str, re, repl), replace(str, old, replacement), replicate(str, N), reverse(str), rightstr(str, N), rtrim(str, [chars]), sparkline(value, [upper]), spooky_hash(str), startswith(str, prefix), strfilter(source, include), substr(str, start, [size]), timezone(tz, ts), trim(str, [chars]), unicode(X), unparse_url(obj), upper(str)


yaml_to_json(yaml)

Convert a YAML document to a JSON-encoded string

PRQL Name: yaml.to_json

Parameters
  • yaml* — The YAML value to convert to JSON.

Examples

To convert the document “abc: def”:

;SELECT yaml_to_json('abc: def')
{"abc": "def"}
See Also

jget(json, ptr, [default]), json_array_length(X, [P]), json_array(X), json_concat(json, value), json_contains(json, value), json_each(X, [P]), json_extract(X, P), json_group_array(value), json_group_object(name, value), json_insert(X, P, Y), json_object(N, V), json_quote(X), json_remove(X, P), json_replace(X, P, Y), json_set(X, P, Y), json_tree(X, [P]), json_type(X, [P]), json_valid(X), json(X)


zeroblob(N)

Returns a BLOB consisting of N bytes of 0x00.

Parameters
  • N* — The size of the BLOB.


;.dump path table


;.msgformats

Executes a query that will summarize the different message formats found in the logs


;.read path


;.schema name

Switch to the SCHEMA view that contains a dump of the current database schema

Parameters
  • name* — The name of a table to jump to


aggregate expr

PRQL transform to summarize many rows into one

Parameters
  • expr* — The aggregate expression(s)

Examples

To group values into a JSON array:

;from [{a=1}, {a=2}] | aggregate { arr = json.group_array a }
[1,2]
See Also

append table, derive column, filter expr, from table, group key_columns pipeline, join [side:inner] table condition, select expr, sort expr, take n_or_range, stats.average_of col, stats.by col values, stats.count_by column, stats.hist col [slice:’1h’] [top:10], stats.sum_of col, utils.distinct col


append table


derive column

PRQL transform to derive one or more columns

Parameters
  • column* — The new column

Examples

To add a column that is a multiplication of another:

;from [{a=1}, {a=2}] | derive b = a * 2
    a          b
         1          2
         2          4
See Also

aggregate expr, append table, filter expr, from table, group key_columns pipeline, join [side:inner] table condition, select expr, sort expr, take n_or_range, stats.average_of col, stats.by col values, stats.count_by column, stats.hist col [slice:’1h’] [top:10], stats.sum_of col, utils.distinct col


filter expr

PRQL transform to pick rows based on their values

Parameters
  • expr* — The expression to evaluate over each row

Examples

To pick rows where ‘a’ is greater than one:

;from [{a=1}, {a=2}] | filter a > 1
2
See Also

aggregate expr, append table, derive column, from table, group key_columns pipeline, join [side:inner] table condition, select expr, sort expr, take n_or_range, stats.average_of col, stats.by col values, stats.count_by column, stats.hist col [slice:’1h’] [top:10], stats.sum_of col, utils.distinct col


from table

PRQL command to specify a data source

Parameters
  • table* — The table to use as a source

Examples

To pull data from the ‘http_status_codes’ database table:

;from http_status_codes | take 3
  status       message
       100 Continue
       101 Switchiotocols
       102 Processing

To use an array literal as a source:

;from [{ col1=1, col2='abc' }, { col1=2, col2='def' }]
   col1    col2
         1 abc
         2 def
See Also

aggregate expr, append table, derive column, filter expr, group key_columns pipeline, join [side:inner] table condition, select expr, sort expr, take n_or_range, stats.average_of col, stats.by col values, stats.count_by column, stats.hist col [slice:’1h’] [top:10], stats.sum_of col, utils.distinct col


group key_columns pipeline

PRQL transform to partition rows into groups

Parameters
  • key_columns* — The columns that define the group

  • pipeline* — The pipeline to execute over a group

Examples

To group by log_level and count the rows in each partition:

;from lnav_example_log | group { log_level } (aggregate { count this })
log_level  COUNT(*)
debug              1
info               1
warn               1
error              1
See Also

aggregate expr, append table, derive column, filter expr, from table, join [side:inner] table condition, select expr, sort expr, take n_or_range, stats.average_of col, stats.by col values, stats.count_by column, stats.hist col [slice:’1h’] [top:10], stats.sum_of col, utils.distinct col


join [side:inner] table condition

PRQL transform to add columns from another table

Parameters
  • side — Specifies which rows to include

  • table* — The other table to join with the current rows

  • condition* — The condition used to join rows

See Also

aggregate expr, append table, derive column, filter expr, from table, group key_columns pipeline, select expr, sort expr, take n_or_range, stats.average_of col, stats.by col values, stats.count_by column, stats.hist col [slice:’1h’] [top:10], stats.sum_of col, utils.distinct col


select expr

PRQL transform to pick and compute columns

Parameters
  • expr* — The columns to include in the result set

Examples

To pick the ‘b’ column from the rows:

;from [{a=1, b='abc'}, {a=2, b='def'}] | select b
 b
abc
def

To compute a new column from an input:

;from [{a=1}, {a=2}] | select b = a * 2
    b
         2
         4
See Also

aggregate expr, append table, derive column, filter expr, from table, group key_columns pipeline, join [side:inner] table condition, sort expr, take n_or_range, stats.average_of col, stats.by col values, stats.count_by column, stats.hist col [slice:’1h’] [top:10], stats.sum_of col, utils.distinct col


sort expr

PRQL transform to sort rows

Parameters
  • expr* — The values to use when ordering the result set

Examples

To sort the rows in descending order:

;from [{a=1}, {a=2}] | sort {-a}
    a
         2
         1
See Also

aggregate expr, append table, derive column, filter expr, from table, group key_columns pipeline, join [side:inner] table condition, select expr, take n_or_range, stats.average_of col, stats.by col values, stats.count_by column, stats.hist col [slice:’1h’] [top:10], stats.sum_of col, utils.distinct col


stats.average_of col

Compute the average of col

Parameters
  • col* — The column to average

Examples

To get the average of a:

;from [{a=1}, {a=1}, {a=2}] | stats.average_of a
1.3333333333333333
See Also

aggregate expr, append table, derive column, filter expr, from table, group key_columns pipeline, join [side:inner] table condition, select expr, sort expr, take n_or_range, stats.by col values, stats.count_by column, stats.hist col [slice:’1h’] [top:10], stats.sum_of col, utils.distinct col


stats.by col values

A shorthand for grouping and aggregating

Parameters
  • col* — The column to sum

  • values* — The aggregations to perform

Examples

To partition by a and get the sum of b:

;from [{a=1, b=1}, {a=1, b=1}, {a=2, b=1}] | stats.by a {sum b}
    a      COALESC(b), 0)
         1               2
         2               1
See Also

aggregate expr, append table, derive column, filter expr, from table, group key_columns pipeline, join [side:inner] table condition, select expr, sort expr, take n_or_range, stats.average_of col, stats.count_by column, stats.hist col [slice:’1h’] [top:10], stats.sum_of col, utils.distinct col


stats.count_by column

Partition rows and count the number of rows in each partition

Parameters
  • column — The columns to group by

Examples

To count rows for a particular value of column ‘a’:

;from [{a=1}, {a=1}, {a=2}] | stats.count_by a
    a        total
         1          2
         2          1
See Also

aggregate expr, append table, derive column, filter expr, from table, group key_columns pipeline, join [side:inner] table condition, select expr, sort expr, take n_or_range, stats.average_of col, stats.by col values, stats.hist col [slice:’1h’] [top:10], stats.sum_of col, utils.distinct col


stats.hist col [slice:’1h’] [top:10]

Count the top values per bucket of time

Parameters
  • col* — The column to count

  • slice — The time slice

  • top — The limit on the number of values to report

Examples

To chart the values of ex_procname over time:

;from lnav_example_log | stats.hist ex_procname
    tslice             v
2017-02:00.000 {"gw":3,"hw":1}
See Also

aggregate expr, append table, derive column, filter expr, from table, group key_columns pipeline, join [side:inner] table condition, select expr, sort expr, take n_or_range, stats.average_of col, stats.by col values, stats.count_by column, stats.sum_of col, utils.distinct col


stats.sum_of col


take n_or_range

PRQL command to pick rows based on their position

Parameters
  • n_or_range* — The number of rows or range

Examples

To pick the first row:

;from [{a=1}, {a=2}, {a=3}] | take 1
1

To pick the second and third rows:

;from [{a=1}, {a=2}, {a=3}] | take 2..3
    a
         2
         3
See Also

aggregate expr, append table, derive column, filter expr, from table, group key_columns pipeline, join [side:inner] table condition, select expr, sort expr, stats.average_of col, stats.by col values, stats.count_by column, stats.hist col [slice:’1h’] [top:10], stats.sum_of col, utils.distinct col


utils.distinct col

A shorthand for getting distinct values of col

Parameters
  • col* — The column to sum

Examples

To get the distinct values of a:

;from [{a=1}, {a=1}, {a=2}] | utils.distinct a
    a
         1
         2
See Also

aggregate expr, append table, derive column, filter expr, from table, group key_columns pipeline, join [side:inner] table condition, select expr, sort expr, take n_or_range, stats.average_of col, stats.by col values, stats.count_by column, stats.hist col [slice:’1h’] [top:10], stats.sum_of col