Date/Time and Interval Functions and Operators

Date/Time and Interval Functions and Operators

Elasticsearch SQL offers a wide range of facilities for performing date/time manipulations.

Intervals

A common requirement when dealing with date/time in general revolves around the notion of interval, a topic that is worth exploring in the context of Elasticsearch and Elasticsearch SQL.

Elasticsearch has comprehensive support for date math both inside index names and queries. Inside Elasticsearch SQL the former is supported as is by passing the expression in the table name, while the latter is supported through the standard SQL INTERVAL.

The table below shows the mapping between Elasticsearch and Elasticsearch SQL:

INTERVAL allows either YEAR and MONTH to be mixed together or DAY, HOUR, MINUTE and SECOND.

Elasticsearch SQL accepts also the plural for each time unit (e.g. both YEAR and YEARS are valid).

Example of the possible combinations below:

Comparison

Date/time fields can be compared to date math expressions with the equality (=) and IN operators:

SELECT hire_date FROM emp WHERE hire_date = '1987-03-01||+4y/y';
       hire_date
------------------------
1991-01-26T00:00:00.000Z
1991-10-22T00:00:00.000Z
1991-09-01T00:00:00.000Z
1991-06-26T00:00:00.000Z
1991-08-30T00:00:00.000Z
1991-12-01T00:00:00.000Z

SELECT hire_date FROM emp WHERE hire_date IN ('1987-03-01||+2y/M', '1987-03-01||+3y/M');
       hire_date
------------------------
1989-03-31T00:00:00.000Z
1990-03-02T00:00:00.000Z

Operators

Basic arithmetic operators (+, -, *) support date/time parameters as indicated below:

SELECT INTERVAL 1 DAY + INTERVAL 53 MINUTES AS result;
    result
---------------
+1 00:53:00

SELECT CAST('1969-05-13T12:34:56' AS DATETIME) + INTERVAL 49 YEARS AS result;
       result
--------------------
2018-05-13T12:34:56Z

SELECT - INTERVAL '49-1' YEAR TO MONTH result;
    result
---------------
-49-1

SELECT INTERVAL '1' DAY - INTERVAL '2' HOURS AS result;
    result
---------------
+0 22:00:00

SELECT CAST('2018-05-13T12:34:56' AS DATETIME) - INTERVAL '2-8' YEAR TO MONTH AS result;
       result
--------------------
2015-09-13T12:34:56Z

SELECT -2 * INTERVAL '3' YEARS AS result;
    result
---------------
-6-0

Functions

Functions that target date/time.

CURRENT_DATE/CURDATE

Synopsis:

CURRENT_DATE
CURRENT_DATE()
CURDATE()

Input: none

Output: date

Description: Returns the date (no time part) when the current query reached the server. It can be used both as a keyword: CURRENT_DATE or as a function with no arguments: CURRENT_DATE().

Unlike CURRENT_DATE, CURDATE() can only be used as a function with no arguments and not as a keyword.

This method always returns the same value for its every occurrence within the same query.

SELECT CURRENT_DATE AS result;
         result
------------------------
2018-12-12

SELECT CURRENT_DATE() AS result;
         result
------------------------
2018-12-12

SELECT CURDATE() AS result;
         result
------------------------
2018-12-12

Typically, this function (as well as its twin TODAY()) function is used for relative date filtering:

SELECT first_name FROM emp WHERE hire_date > TODAY() - INTERVAL 35 YEARS ORDER BY first_name ASC LIMIT 5;
 first_name
------------
Alejandro
Amabile
Anoosh
Basil
Brendon

CURRENT_TIME/CURTIME

Synopsis:

CURRENT_TIME
CURRENT_TIME([precision]) 
CURTIME

Input:

Output: time

Description: Returns the time when the current query reached the server. As a function, CURRENT_TIME() accepts precision as an optional parameter for rounding the second fractional digits (nanoseconds). The default precision is 3, meaning a milliseconds precision current time will be returned.

This method always returns the same value for its every occurrence within the same query.

SELECT CURRENT_TIME AS result;
         result
------------------------
12:31:27.237Z

SELECT CURRENT_TIME() AS result;
         result
------------------------
12:31:27.237Z

SELECT CURTIME() AS result;
         result
------------------------
12:31:27.237Z

SELECT CURRENT_TIME(1) AS result;
         result
------------------------
12:31:27.2Z

Typically, this function is used for relative date/time filtering:

SELECT first_name FROM emp WHERE CAST(hire_date AS TIME) > CURRENT_TIME() - INTERVAL 20 MINUTES ORDER BY first_name ASC LIMIT 5;
  first_name
---------------
Alejandro
Amabile
Anneke
Anoosh
Arumugam

Currently, using a precision greater than 6 doesn’t make any difference to the output of the function as the maximum number of second fractional digits returned is 6.

CURRENT_TIMESTAMP

Synopsis:

CURRENT_TIMESTAMP
CURRENT_TIMESTAMP([precision])

Input:

Output: date/time

Description: Returns the date/time when the current query reached the server. As a function, CURRENT_TIMESTAMP() accepts precision as an optional parameter for rounding the second fractional digits (nanoseconds). The default precision is 3, meaning a milliseconds precision current date/time will be returned.

This method always returns the same value for its every occurrence within the same query.

SELECT CURRENT_TIMESTAMP AS result;
         result
------------------------
2018-12-12T14:48:52.448Z

SELECT CURRENT_TIMESTAMP() AS result;
         result
------------------------
2018-12-12T14:48:52.448Z

SELECT CURRENT_TIMESTAMP(1) AS result;
         result
------------------------
2018-12-12T14:48:52.4Z

Typically, this function (as well as its twin NOW()) function is used for relative date/time filtering:

SELECT first_name FROM emp WHERE hire_date > NOW() - INTERVAL 100 YEARS ORDER BY first_name ASC LIMIT 5;
  first_name
---------------
Alejandro
Amabile
Anneke
Anoosh
Arumugam

Currently, using a precision greater than 6 doesn’t make any difference to the output of the function as the maximum number of second fractional digits returned is 6.

DATE_ADD/DATEADD/TIMESTAMP_ADD/TIMESTAMPADD

Synopsis:

DATE_ADD(
    string_exp, 
    integer_exp, 
    datetime_exp)

Input:

Output: datetime

Description: Add the given number of date/time units to a date/datetime. If the number of units is negative then it’s subtracted from the date/datetime.

If the second argument is a long there is possibility of truncation since an integer value will be extracted and used from that long.

SELECT DATE_ADD('years', 10, '2019-09-04T11:22:33.000Z'::datetime) AS "+10 years";
      +10 years
------------------------
2029-09-04T11:22:33.000Z

SELECT DATE_ADD('week', 10, '2019-09-04T11:22:33.000Z'::datetime) AS "+10 weeks";
      +10 weeks
------------------------
2019-11-13T11:22:33.000Z

SELECT DATE_ADD('seconds', -1234, '2019-09-04T11:22:33.000Z'::datetime) AS "-1234 seconds";
      -1234 seconds
------------------------
2019-09-04T11:01:59.000Z

SELECT DATE_ADD('qq', -417, '2019-09-04'::date) AS "-417 quarters";
      -417 quarters
------------------------
1915-06-04T00:00:00.000Z

SELECT DATE_ADD('minutes', 9235, '2019-09-04'::date) AS "+9235 minutes";
      +9235 minutes
------------------------
2019-09-10T09:55:00.000Z

DATE_DIFF/DATEDIFF/TIMESTAMP_DIFF/TIMESTAMPDIFF

Synopsis:

DATE_DIFF(
    string_exp, 
    datetime_exp, 
    datetime_exp)

Input:

Output: integer

Description: Subtract the second argument from the third argument and return their difference in multiples of the unit specified in the first argument. If the second argument (start) is greater than the third argument (end), then negative values are returned.

SELECT DATE_DIFF('years', '2019-09-04T11:22:33.000Z'::datetime, '2032-09-04T22:33:11.000Z'::datetime) AS "diffInYears";
      diffInYears
------------------------
13

SELECT DATE_DIFF('week', '2019-09-04T11:22:33.000Z'::datetime, '2016-12-08T22:33:11.000Z'::datetime) AS "diffInWeeks";
      diffInWeeks
------------------------
-143

SELECT DATE_DIFF('seconds', '2019-09-04T11:22:33.123Z'::datetime, '2019-07-12T22:33:11.321Z'::datetime) AS "diffInSeconds";
      diffInSeconds
------------------------
-4625362

SELECT DATE_DIFF('qq', '2019-09-04'::date, '2025-04-25'::date) AS "diffInQuarters";
      diffInQuarters
------------------------
23

For hour and minute, DATEDIFF doesn’t do any rounding, but instead first truncates the more detailed time fields on the 2 dates to zero and then calculates the subtraction.

SELECT DATEDIFF('hours', '2019-11-10T12:10:00.000Z'::datetime, '2019-11-10T23:59:59.999Z'::datetime) AS "diffInHours";
      diffInHours
------------------------
11

SELECT DATEDIFF('minute', '2019-11-10T12:10:00.000Z'::datetime, '2019-11-10T12:15:59.999Z'::datetime) AS "diffInMinutes";
      diffInMinutes
------------------------
5

SELECT DATE_DIFF('minutes', '2019-09-04'::date, '2015-08-17T22:33:11.567Z'::datetime) AS "diffInMinutes";
      diffInMinutes
------------------------
-2128407

DATE_FORMAT

Synopsis:

DATE_FORMAT(
    date_exp/datetime_exp/time_exp, 
    string_exp)

Input:

Output: string

Description: Returns the date/datetime/time as a string using the format specified in the 2nd argument. The formatting pattern is one of the specifiers used in the MySQL DATE_FORMAT() function.

If the 1st argument is of type time, then pattern specified by the 2nd argument cannot contain date related units (e.g. dd, MM, yyyy, etc.). If it contains such units an error is returned. Ranges for month and day specifiers (%c, %D, %d, %e, %m) start at one, unlike MySQL, where they start at zero, due to the fact that MySQL permits the storing of incomplete dates such as 2014-00-00. Elasticsearch in this case returns an error.

SELECT DATE_FORMAT(CAST('2020-04-05' AS DATE), '%d/%m/%Y') AS "date";
      date
------------------
05/04/2020

SELECT DATE_FORMAT(CAST('2020-04-05T11:22:33.987654' AS DATETIME), '%d/%m/%Y %H:%i:%s.%f') AS "datetime";
      datetime
------------------
05/04/2020 11:22:33.987654

SELECT DATE_FORMAT(CAST('23:22:33.987' AS TIME), '%H %i %s.%f') AS "time";
      time
------------------
23 22 33.987000

DATE_PARSE

Synopsis:

DATE_PARSE(
    string_exp, 
    string_exp)

Input:

Output: date

Description: Returns a date by parsing the 1st argument using the format specified in the 2nd argument. The parsing format pattern used is the one from java.time.format.DateTimeFormatter.

If the parsing pattern does not contain all valid date units (e.g. HH:mm:ss, dd-MM HH:mm:ss, etc.) an error is returned as the function needs to return a value of date type which will contain date part.

SELECT DATE_PARSE('07/04/2020', 'dd/MM/yyyy') AS "date";
   date
-----------
2020-04-07

The resulting date will have the time zone specified by the user through the time_zone/timezone REST/driver parameters with no conversion applied.

{
    "query" : "SELECT DATE_PARSE('07/04/2020', 'dd/MM/yyyy') AS \"date\"",
    "time_zone" : "Europe/Athens"
}
   date
------------
2020-04-07T00:00:00.000+03:00

DATETIME_FORMAT

Synopsis:

DATETIME_FORMAT(
    date_exp/datetime_exp/time_exp, 
    string_exp)

Input:

Output: string

Description: Returns the date/datetime/time as a string using the format specified in the 2nd argument. The formatting pattern used is the one from java.time.format.DateTimeFormatter.

If the 1st argument is of type time, then pattern specified by the 2nd argument cannot contain date related units (e.g. dd, MM, yyyy, etc.). If it contains such units an error is returned.

SELECT DATETIME_FORMAT(CAST('2020-04-05' AS DATE), 'dd/MM/yyyy') AS "date";
      date
------------------
05/04/2020

SELECT DATETIME_FORMAT(CAST('2020-04-05T11:22:33.987654' AS DATETIME), 'dd/MM/yyyy HH:mm:ss.SS') AS "datetime";
      datetime
------------------
05/04/2020 11:22:33.98

SELECT DATETIME_FORMAT(CAST('11:22:33.987' AS TIME), 'HH mm ss.S') AS "time";
      time
------------------
11 22 33.9

DATETIME_PARSE

Synopsis:

DATETIME_PARSE(
    string_exp, 
    string_exp)

Input:

Output: datetime

Description: Returns a datetime by parsing the 1st argument using the format specified in the 2nd argument. The parsing format pattern used is the one from java.time.format.DateTimeFormatter.

If the parsing pattern contains only date or only time units (e.g. dd/MM/yyyy, HH:mm:ss, etc.) an error is returned as the function needs to return a value of datetime type which must contain both.

SELECT DATETIME_PARSE('07/04/2020 10:20:30.123', 'dd/MM/yyyy HH:mm:ss.SSS') AS "datetime";
      datetime
------------------------
2020-04-07T10:20:30.123Z

SELECT DATETIME_PARSE('10:20:30 07/04/2020 Europe/Berlin', 'HH:mm:ss dd/MM/yyyy VV') AS "datetime";
      datetime
------------------------
2020-04-07T08:20:30.000Z

If timezone is not specified in the datetime string expression and the parsing pattern, the resulting datetime will have the time zone specified by the user through the time_zone/timezone REST/driver parameters with no conversion applied.

{
    "query" : "SELECT DATETIME_PARSE('10:20:30 07/04/2020', 'HH:mm:ss dd/MM/yyyy') AS \"datetime\"",
    "time_zone" : "Europe/Athens"
}
      datetime
-----------------------------
2020-04-07T10:20:30.000+03:00

TIME_PARSE

Synopsis:

TIME_PARSE(
    string_exp, 
    string_exp)

Input:

Output: time

Description: Returns a time by parsing the 1st argument using the format specified in the 2nd argument. The parsing format pattern used is the one from java.time.format.DateTimeFormatter.

If the parsing pattern contains only date units (e.g. dd/MM/yyyy) an error is returned as the function needs to return a value of time type which will contain only time.

SELECT TIME_PARSE('10:20:30.123', 'HH:mm:ss.SSS') AS "time";
     time
---------------
10:20:30.123Z

SELECT TIME_PARSE('10:20:30-01:00', 'HH:mm:ssXXX') AS "time";
     time
---------------
11:20:30.000Z

If timezone is not specified in the time string expression and the parsing pattern, the resulting time will have the offset of the time zone specified by the user through the time_zone/timezone REST/driver parameters at the Unix epoch date (1970-01-01) with no conversion applied.

{
    "query" : "SELECT DATETIME_PARSE('10:20:30', 'HH:mm:ss') AS \"time\"",
    "time_zone" : "Europe/Athens"
}
      time
------------------------------------
10:20:30.000+02:00

DATE_PART/DATEPART

Synopsis:

DATE_PART(
    string_exp, 
    datetime_exp)

Input:

Output: integer

Description: Extract the specified unit from a date/datetime. It’s similar to EXTRACT but with different names and aliases for the units and provides more options (e.g.: TZOFFSET).

SELECT DATE_PART('year', '2019-09-22T11:22:33.123Z'::datetime) AS "years";
   years
----------
2019

SELECT DATE_PART('mi', '2019-09-04T11:22:33.123Z'::datetime) AS mins;
   mins
-----------
22

SELECT DATE_PART('quarters', CAST('2019-09-24' AS DATE)) AS quarter;
   quarter
-------------
3

SELECT DATE_PART('month', CAST('2019-09-24' AS DATE)) AS month;
   month
-------------
9

For week and weekday the unit is extracted using the non-ISO calculation, which means that a given week is considered to start from Sunday, not Monday.

SELECT DATE_PART('week', '2019-09-22T11:22:33.123Z'::datetime) AS week;
   week
----------
39

The tzoffset returns the total number of minutes (signed) that represent the time zone’s offset.

SELECT DATE_PART('tzoffset', '2019-09-04T11:22:33.123+05:15'::datetime) AS tz_mins;
   tz_mins
--------------
315

SELECT DATE_PART('tzoffset', '2019-09-04T11:22:33.123-03:49'::datetime) AS tz_mins;
   tz_mins
--------------
-229

DATE_TRUNC/DATETRUNC

Synopsis:

DATE_TRUNC(
    string_exp, 
    datetime_exp/interval_exp)

Input:

Output: datetime/interval

Description: Truncate the date/datetime/interval to the specified unit by setting all fields that are less significant than the specified one to zero (or one, for day, day of week and month). If the first argument is week and the second argument is of interval type, an error is thrown since the interval data type doesn’t support a week time unit.

SELECT DATE_TRUNC('millennium', '2019-09-04T11:22:33.123Z'::datetime) AS millennium;
      millennium
------------------------
2000-01-01T00:00:00.000Z

SELECT DATETRUNC('week', '2019-08-24T11:22:33.123Z'::datetime) AS week;
      week
------------------------
2019-08-19T00:00:00.000Z

SELECT DATE_TRUNC('mi', '2019-09-04T11:22:33.123Z'::datetime) AS mins;
      mins
------------------------
2019-09-04T11:22:00.000Z

SELECT DATE_TRUNC('decade', CAST('2019-09-04' AS DATE)) AS decades;
      decades
------------------------
2010-01-01T00:00:00.000Z

SELECT DATETRUNC('quarters', CAST('2019-09-04' AS DATE)) AS quarter;
      quarter
------------------------
2019-07-01T00:00:00.000Z

SELECT DATE_TRUNC('centuries', INTERVAL '199-5' YEAR TO MONTH) AS centuries;
      centuries
------------------
 +100-0

SELECT DATE_TRUNC('hours', INTERVAL '17 22:13:12' DAY TO SECONDS) AS hour;
      hour
------------------
+17 22:00:00

SELECT DATE_TRUNC('days', INTERVAL '19 15:24:19' DAY TO SECONDS) AS day;
      day
------------------
+19 00:00:00

FORMAT

Synopsis:

FORMAT(
    date_exp/datetime_exp/time_exp, 
    string_exp)

Input:

Output: string

Description: Returns the date/datetime/time as a string using the format specified in the 2nd argument. The formatting pattern used is the one from Microsoft SQL Server Format Specification.

If the 1st argument is of type time, then pattern specified by the 2nd argument cannot contain date related units (e.g. dd, MM, yyyy, etc.). If it contains such units an error is returned.
Format specifier F will be working similar to format specifier f. It will return the fractional part of seconds, and the number of digits will be same as of the number of Fs provided as input (up to 9 digits). Result will contain 0 appended in the end to match with number of F provided. e.g.: for a time part 10:20:30.1234 and pattern HH:mm:ss.FFFFFF, the output string of the function would be: 10:20:30.123400.
Format specifier y will return year-of-era instead of one/two low-order digits. eg.: For year 2009, y will be returning 2009 instead of 9. For year 43, y format specifier will return 43. - Special characters like " , \ and % will be returned as it is without any change. eg.: formatting date 17-sep-2020 with %M will return %9

SELECT FORMAT(CAST('2020-04-05' AS DATE), 'dd/MM/yyyy') AS "date";
      date
------------------
05/04/2020

SELECT FORMAT(CAST('2020-04-05T11:22:33.987654' AS DATETIME), 'dd/MM/yyyy HH:mm:ss.ff') AS "datetime";
      datetime
------------------
05/04/2020 11:22:33.98

SELECT FORMAT(CAST('11:22:33.987' AS TIME), 'HH mm ss.f') AS "time";
      time
------------------
11 22 33.9

TO_CHAR

Synopsis:

TO_CHAR(
    date_exp/datetime_exp/time_exp, 
    string_exp)

Input:

Output: string

Description: Returns the date/datetime/time as a string using the format specified in the 2nd argument. The formatting pattern conforms to PostgreSQL Template Patterns for Date/Time Formatting.

If the 1st argument is of type time, then the pattern specified by the 2nd argument cannot contain date related units (e.g. dd, MM, YYYY, etc.). If it contains such units an error is returned.
The result of the patterns TZ and tz (time zone abbreviations) in some cases differ from the results returned by the TO_CHAR in PostgreSQL. The reason is that the time zone abbreviations specified by the JDK are different from the ones specified by PostgreSQL. This function might show an actual time zone abbreviation instead of the generic LMT or empty string or offset returned by the PostgreSQL implementation. The summer/daylight markers might also differ between the two implementations (e.g. will show HT instead of HST for Hawaii).
The FX, TM, SP pattern modifiers are not supported and will show up as FX, TM, SP literals in the output.

SELECT TO_CHAR(CAST('2020-04-05' AS DATE), 'DD/MM/YYYY') AS "date";
      date
------------------
05/04/2020

SELECT TO_CHAR(CAST('2020-04-05T11:22:33.987654' AS DATETIME), 'DD/MM/YYYY HH24:MI:SS.FF2') AS "datetime";
      datetime
------------------
05/04/2020 11:22:33.98

SELECT TO_CHAR(CAST('23:22:33.987' AS TIME), 'HH12 MI SS.FF1') AS "time";
      time
------------------
11 22 33.9

DAY_OF_MONTH/DOM/DAY

Synopsis:

DAY_OF_MONTH(datetime_exp)

Input:

Output: integer

Description: Extract the day of the month from a date/datetime.

SELECT DAY_OF_MONTH(CAST('2018-02-19T10:23:27Z' AS TIMESTAMP)) AS day;
      day
---------------
19

DAY_OF_WEEK/DAYOFWEEK/DOW

Synopsis:

DAY_OF_WEEK(datetime_exp)

Input:

Output: integer

Description: Extract the day of the week from a date/datetime. Sunday is 1, Monday is 2, etc.

SELECT DAY_OF_WEEK(CAST('2018-02-19T10:23:27Z' AS TIMESTAMP)) AS day;
      day
---------------
2

DAY_OF_YEAR/DOY

Synopsis:

DAY_OF_YEAR(datetime_exp)

Input:

Output: integer

Description: Extract the day of the year from a date/datetime.

SELECT DAY_OF_YEAR(CAST('2018-02-19T10:23:27Z' AS TIMESTAMP)) AS day;
      day
---------------
50

DAY_NAME/DAYNAME

Synopsis:

DAY_NAME(datetime_exp)

Input:

Output: string

Description: Extract the day of the week from a date/datetime in text format (Monday, Tuesday…​).

SELECT DAY_NAME(CAST('2018-02-19T10:23:27Z' AS TIMESTAMP)) AS day;
      day
---------------
Monday

HOUR_OF_DAY/HOUR

Synopsis:

HOUR_OF_DAY(datetime_exp)

Input:

Output: integer

Description: Extract the hour of the day from a date/datetime.

SELECT HOUR_OF_DAY(CAST('2018-02-19T10:23:27Z' AS TIMESTAMP)) AS hour;
     hour
---------------
10

ISO_DAY_OF_WEEK/ISODAYOFWEEK/ISODOW/IDOW

Synopsis:

ISO_DAY_OF_WEEK(datetime_exp)

Input:

Output: integer

Description: Extract the day of the week from a date/datetime, following the ISO 8601 standard. Monday is 1, Tuesday is 2, etc.

SELECT ISO_DAY_OF_WEEK(CAST('2018-02-19T10:23:27Z' AS TIMESTAMP)) AS day;
      day
---------------
1

ISO_WEEK_OF_YEAR/ISOWEEKOFYEAR/ISOWEEK/IWOY/IW

Synopsis:

ISO_WEEK_OF_YEAR(datetime_exp)

Input:

Output: integer

Description: Extract the week of the year from a date/datetime, following ISO 8601 standard. The first week of a year is the first week with a majority (4 or more) of its days in January.

SELECT ISO_WEEK_OF_YEAR(CAST('2018-02-19T10:23:27Z' AS TIMESTAMP)) AS week;
     week
---------------
8

MINUTE_OF_DAY

Synopsis:

MINUTE_OF_DAY(datetime_exp)

Input:

Output: integer

Description: Extract the minute of the day from a date/datetime.

SELECT MINUTE_OF_DAY(CAST('2018-02-19T10:23:27Z' AS TIMESTAMP)) AS minute;
    minute
---------------
623

MINUTE_OF_HOUR/MINUTE

Synopsis:

MINUTE_OF_HOUR(datetime_exp)

Input:

Output: integer

Description: Extract the minute of the hour from a date/datetime.

SELECT MINUTE_OF_HOUR(CAST('2018-02-19T10:23:27Z' AS TIMESTAMP)) AS minute;
    minute
---------------
23

MONTH_OF_YEAR/MONTH

Synopsis:

MONTH(datetime_exp)

Input:

Output: integer

Description: Extract the month of the year from a date/datetime.

SELECT MONTH_OF_YEAR(CAST('2018-02-19T10:23:27Z' AS TIMESTAMP)) AS month;
     month
---------------
2

MONTH_NAME/MONTHNAME

Synopsis:

MONTH_NAME(datetime_exp)

Input:

Output: string

Description: Extract the month from a date/datetime in text format (January, February…​).

SELECT MONTH_NAME(CAST('2018-02-19T10:23:27Z' AS TIMESTAMP)) AS month;
     month
---------------
February

NOW

Synopsis:

NOW()

Input: none

Output: datetime

Description: This function offers the same functionality as CURRENT_TIMESTAMP() function: returns the datetime when the current query reached the server. This method always returns the same value for its every occurrence within the same query.

SELECT NOW() AS result;
         result
------------------------
2018-12-12T14:48:52.448Z

Typically, this function (as well as its twin CURRENT_TIMESTAMP()) function is used for relative date/time filtering:

SELECT first_name FROM emp WHERE hire_date > NOW() - INTERVAL 100 YEARS ORDER BY first_name ASC LIMIT 5;
  first_name
---------------
Alejandro
Amabile
Anneke
Anoosh
Arumugam

SECOND_OF_MINUTE/SECOND

Synopsis:

SECOND_OF_MINUTE(datetime_exp)

Input:

Output: integer

Description: Extract the second of the minute from a date/datetime.

SELECT SECOND_OF_MINUTE(CAST('2018-02-19T10:23:27Z' AS TIMESTAMP)) AS second;
    second
---------------
27

QUARTER

Synopsis:

QUARTER(datetime_exp)

Input:

Output: integer

Description: Extract the year quarter the date/datetime falls in.

SELECT QUARTER(CAST('2018-02-19T10:23:27Z' AS TIMESTAMP)) AS quarter;
    quarter
---------------
1

TODAY

Synopsis:

TODAY()

Input: none

Output: date

Description: This function offers the same functionality as CURRENT_DATE() function: returns the date when the current query reached the server. This method always returns the same value for its every occurrence within the same query.

SELECT TODAY() AS result;
         result
------------------------
2018-12-12

Typically, this function (as well as its twin CURRENT_TIMESTAMP()) function is used for relative date filtering:

SELECT first_name FROM emp WHERE hire_date > TODAY() - INTERVAL 35 YEARS ORDER BY first_name ASC LIMIT 5;
 first_name
------------
Alejandro
Amabile
Anoosh
Basil
Brendon

WEEK_OF_YEAR/WEEK

Synopsis:

WEEK_OF_YEAR(datetime_exp)

Input:

Output: integer

Description: Extract the week of the year from a date/datetime.

SELECT WEEK(CAST('1988-01-05T09:22:10Z' AS TIMESTAMP)) AS week, ISOWEEK(CAST('1988-01-05T09:22:10Z' AS TIMESTAMP)) AS isoweek;
      week     |   isoweek
---------------+---------------
2              |1

YEAR

Synopsis:

YEAR(datetime_exp)

Input:

Output: integer

Description: Extract the year from a date/datetime.

SELECT YEAR(CAST('2018-02-19T10:23:27Z' AS TIMESTAMP)) AS year;
     year
---------------
2018

EXTRACT

Synopsis:

EXTRACT(
    datetime_function  
    FROM datetime_exp)

Input:

Output: integer

Description: Extract fields from a date/datetime by specifying the name of a datetime function. The following

SELECT EXTRACT(DAY_OF_YEAR FROM CAST('2018-02-19T10:23:27Z' AS TIMESTAMP)) AS day;
      day
---------------
50

is the equivalent to

SELECT DAY_OF_YEAR(CAST('2018-02-19T10:23:27Z' AS TIMESTAMP)) AS day;
      day
---------------
50