This section describes the functions that can be used to manipulate temporal values. See Section 13.2, “Date and Time Data Types”, for a description of the range of values each date and time type has and the valid formats in which values may be specified.
Table 14.11 Date and Time Functions
| Name | Description | 
|---|---|
| ADDDATE() | Add time values (intervals) to a date value | 
| ADDTIME() | Add time | 
| CONVERT_TZ() | Convert from one time zone to another | 
| CURDATE() | Return the current date | 
| CURRENT_DATE(),CURRENT_DATE | Synonyms for CURDATE() | 
| CURRENT_TIME(),CURRENT_TIME | Synonyms for CURTIME() | 
| CURRENT_TIMESTAMP(),CURRENT_TIMESTAMP | Synonyms for NOW() | 
| CURTIME() | Return the current time | 
| DATE() | Extract the date part of a date or datetime expression | 
| DATE_ADD() | Add time values (intervals) to a date value | 
| DATE_FORMAT() | Format date as specified | 
| DATE_SUB() | Subtract a time value (interval) from a date | 
| DATEDIFF() | Subtract two dates | 
| DAY() | Synonym for DAYOFMONTH() | 
| DAYNAME() | Return the name of the weekday | 
| DAYOFMONTH() | Return the day of the month (0-31) | 
| DAYOFWEEK() | Return the weekday index of the argument | 
| DAYOFYEAR() | Return the day of the year (1-366) | 
| EXTRACT() | Extract part of a date | 
| FROM_DAYS() | Convert a day number to a date | 
| FROM_UNIXTIME() | Format Unix timestamp as a date | 
| GET_FORMAT() | Return a date format string | 
| HOUR() | Extract the hour | 
| LAST_DAY | Return the last day of the month for the argument | 
| LOCALTIME(),LOCALTIME | Synonym for NOW() | 
| LOCALTIMESTAMP,LOCALTIMESTAMP() | Synonym for NOW() | 
| MAKEDATE() | Create a date from the year and day of year | 
| MAKETIME() | Create time from hour, minute, second | 
| MICROSECOND() | Return the microseconds from argument | 
| MINUTE() | Return the minute from the argument | 
| MONTH() | Return the month from the date passed | 
| MONTHNAME() | Return the name of the month | 
| NOW() | Return the current date and time | 
| PERIOD_ADD() | Add a period to a year-month | 
| PERIOD_DIFF() | Return the number of months between periods | 
| QUARTER() | Return the quarter from a date argument | 
| SEC_TO_TIME() | Converts seconds to 'hh:mm:ss' format | 
| SECOND() | Return the second (0-59) | 
| STR_TO_DATE() | Convert a string to a date | 
| SUBDATE() | Synonym for DATE_SUB() when invoked with three arguments | 
| SUBTIME() | Subtract times | 
| SYSDATE() | Return the time at which the function executes | 
| TIME() | Extract the time portion of the expression passed | 
| TIME_FORMAT() | Format as time | 
| TIME_TO_SEC() | Return the argument converted to seconds | 
| TIMEDIFF() | Subtract time | 
| TIMESTAMP() | With a single argument, this function returns the date or datetime expression; with two arguments, the sum of the arguments | 
| TIMESTAMPADD() | Add an interval to a datetime expression | 
| TIMESTAMPDIFF() | Return the difference of two datetime expressions, using the units specified | 
| TO_DAYS() | Return the date argument converted to days | 
| TO_SECONDS() | Return the date or datetime argument converted to seconds since Year 0 | 
| UNIX_TIMESTAMP() | Return a Unix timestamp | 
| UTC_DATE() | Return the current UTC date | 
| UTC_TIME() | Return the current UTC time | 
| UTC_TIMESTAMP() | Return the current UTC date and time | 
| WEEK() | Return the week number | 
| WEEKDAY() | Return the weekday index | 
| WEEKOFYEAR() | Return the calendar week of the date (1-53) | 
| YEAR() | Return the year | 
| YEARWEEK() | Return the year and week | 
      Here is an example that uses date functions. The following query
      selects all rows with a date_col value
      from within the last 30 days:
    
mysql> SELECT something FROM tbl_name
    -> WHERE DATE_SUB(CURDATE(),INTERVAL 30 DAY) <= date_col;The query also selects rows with dates that lie in the future.
Functions that expect date values usually accept datetime values and ignore the time part. Functions that expect time values usually accept datetime values and ignore the date part.
      Functions that return the current date or time each are evaluated
      only once per query at the start of query execution. This means
      that multiple references to a function such as
      NOW() within a single query always
      produce the same result. (For our purposes, a single query also
      includes a call to a stored program (stored routine, trigger, or
      event) and all subprograms called by that program.) This principle
      also applies to CURDATE(),
      CURTIME(),
      UTC_DATE(),
      UTC_TIME(),
      UTC_TIMESTAMP(), and to any of
      their synonyms.
    
      The CURRENT_TIMESTAMP(),
      CURRENT_TIME(),
      CURRENT_DATE(), and
      FROM_UNIXTIME() functions return
      values in the current session time zone, which is available as the
      session value of the time_zone
      system variable. In addition,
      UNIX_TIMESTAMP() assumes that its
      argument is a datetime value in the session time zone. See
      Section 7.1.15, “MySQL Server Time Zone Support”.
    
      Some date functions can be used with “zero” dates or
      incomplete dates such as '2001-11-00', whereas
      others cannot. Functions that extract parts of dates typically
      work with incomplete dates and thus can return 0 when you might
      otherwise expect a nonzero value. For example:
    
mysql> SELECT DAYOFMONTH('2001-11-00'), MONTH('2005-00-00');
        -> 0, 0
      Other functions expect complete dates and return
      NULL for incomplete dates. These include
      functions that perform date arithmetic or that map parts of dates
      to names. For example:
    
mysql> SELECT DATE_ADD('2006-05-00',INTERVAL 1 DAY);
        -> NULL
mysql> SELECT DAYNAME('2006-05-00');
        -> NULL
      Several functions are strict when passed a
      DATE() function value as their
      argument and reject incomplete dates with a day part of zero:
      CONVERT_TZ(),
      DATE_ADD(),
      DATE_SUB(),
      DAYOFYEAR(),
      TIMESTAMPDIFF(),
      TO_DAYS(),
      TO_SECONDS(),
      WEEK(),
      WEEKDAY(),
      WEEKOFYEAR(),
      YEARWEEK().
    
      Fractional seconds for TIME,
      DATETIME, and TIMESTAMP
      values are supported, with up to microsecond precision. Functions
      that take temporal arguments accept values with fractional
      seconds. Return values from temporal functions include fractional
      seconds as appropriate.
- ADDDATE(,- date,INTERVAL- expr- unit)- ADDDATE(- date,- days)- When invoked with the - INTERVALform of the second argument,- ADDDATE()is a synonym for- DATE_ADD(). The related function- SUBDATE()is a synonym for- DATE_SUB(). For information on the- INTERVAL- unitargument, see Temporal Intervals.- mysql> SELECT DATE_ADD('2008-01-02', INTERVAL 31 DAY); -> '2008-02-02' mysql> SELECT ADDDATE('2008-01-02', INTERVAL 31 DAY); -> '2008-02-02'- When invoked with the - daysform of the second argument, MySQL treats it as an integer number of days to be added to- expr.- mysql> SELECT ADDDATE('2008-01-02', 31); -> '2008-02-02'- This function returns - NULLif- dateor- daysis- NULL.
- ADDTIME()adds- expr2to- expr1and returns the result.- expr1is a time or datetime expression, and- expr2is a time expression. Returns- NULLif- expr1or- expr2is- NULL.- The return type of this function and of the - SUBTIME()function is determined as follows:- If the first argument is a dynamic parameter (such as in a prepared statement), the return type is - TIME.
- Otherwise, the resolved type of the function is derived from the resolved type of the first argument. 
 - mysql> SELECT ADDTIME('2007-12-31 23:59:59.999999', '1 1:1:1.000002'); -> '2008-01-02 01:01:01.000001' mysql> SELECT ADDTIME('01:00:00.999999', '02:00:00.999998'); -> '03:00:01.999997'
- CONVERT_TZ()converts a datetime value- dtfrom the time zone given by- from_tzto the time zone given by- to_tzand returns the resulting value. Time zones are specified as described in Section 7.1.15, “MySQL Server Time Zone Support”. This function returns- NULLif any of the arguments are invalid, or if any of them are- NULL.- On 32-bit platforms, the supported range of values for this function is the same as for the - TIMESTAMPtype (see Section 13.2.1, “Date and Time Data Type Syntax”, for range information). On 64-bit platforms, the maximum supported value is- '3001-01-18 23:59:59.999999'UTC.- Regardless of platform or MySQL version, if the value falls out of the supported range when converted from - from_tzto UTC, no conversion occurs.- mysql> SELECT CONVERT_TZ('2004-01-01 12:00:00','GMT','MET'); -> '2004-01-01 13:00:00' mysql> SELECT CONVERT_TZ('2004-01-01 12:00:00','+00:00','+10:00'); -> '2004-01-01 22:00:00'Note- To use named time zones such as - 'MET'or- 'Europe/Amsterdam', the time zone tables must be properly set up. For instructions, see Section 7.1.15, “MySQL Server Time Zone Support”.
- Returns the current date as a value in - 'or- YYYY-MM-DD'- YYYYMMDDformat, depending on whether the function is used in string or numeric context.- mysql> SELECT CURDATE(); -> '2008-06-13' mysql> SELECT CURDATE() + 0; -> 20080613
- CURRENT_DATEand- CURRENT_DATE()are synonyms for- CURDATE().
- CURRENT_TIME,- CURRENT_TIME([- fsp])- CURRENT_TIMEand- CURRENT_TIME()are synonyms for- CURTIME().
- CURRENT_TIMESTAMP,- CURRENT_TIMESTAMP([- fsp])- CURRENT_TIMESTAMPand- CURRENT_TIMESTAMP()are synonyms for- NOW().
- Returns the current time as a value in - 'hh:mm:ss'or- hhmmssformat, depending on whether the function is used in string or numeric context. The value is expressed in the session time zone.- If the - fspargument is given to specify a fractional seconds precision from 0 to 6, the return value includes a fractional seconds part of that many digits.- mysql> SELECT CURTIME(); +-----------+ | CURTIME() | +-----------+ | 19:25:37 | +-----------+ mysql> SELECT CURTIME() + 0; +---------------+ | CURTIME() + 0 | +---------------+ | 192537 | +---------------+ mysql> SELECT CURTIME(3); +--------------+ | CURTIME(3) | +--------------+ | 19:25:37.840 | +--------------+
- Extracts the date part of the date or datetime expression - expr. Returns- NULLif- expris- NULL.- mysql> SELECT DATE('2003-12-31 01:02:03'); -> '2003-12-31'
- DATEDIFF()returns- expr1−- expr2expressed as a value in days from one date to the other.- expr1and- expr2are date or date-and-time expressions. Only the date parts of the values are used in the calculation.- mysql> SELECT DATEDIFF('2007-12-31 23:59:59','2007-12-30'); -> 1 mysql> SELECT DATEDIFF('2010-11-30 23:59:59','2010-12-31'); -> -31- This function returns - NULLif- expr1or- expr2is- NULL.
- DATE_ADD(,- date,INTERVAL- expr- unit)- DATE_SUB(- date,INTERVAL- expr- unit)- These functions perform date arithmetic. The - dateargument specifies the starting date or datetime value.- expris an expression specifying the interval value to be added or subtracted from the starting date.- expris evaluated as a string; it may start with a- -for negative intervals.- unitis a keyword indicating the units in which the expression should be interpreted.- For more information about temporal interval syntax, including a full list of - unitspecifiers, the expected form of the- exprargument for each- unitvalue, and rules for operand interpretation in temporal arithmetic, see Temporal Intervals.- The return value depends on the arguments: - If - dateis- NULL, the function returns- NULL.
- DATEif the- dateargument is a- DATEvalue and your calculations involve only- YEAR,- MONTH, and- DAYparts (that is, no time parts).
- TIMEif the- dateargument is a- TIMEvalue and the calculations involve only- HOURS,- MINUTES, and- SECONDSparts (that is, no date parts).
- DATETIMEif the first argument is a- DATETIME(or- TIMESTAMP) value, or if the first argument is a- DATEand the- unitvalue uses- HOURS,- MINUTES, or- SECONDS, or if the first argument is of type- TIMEand the- unitvalue uses- YEAR,- MONTH, or- DAY.
- If the first argument is a dynamic parameter (for example, of a prepared statement), its resolved type is - DATEif the second argument is an interval that contains some combination of- YEAR,- MONTH, or- DAYvalues only; otherwise, its type is- DATETIME.
- String otherwise (type - VARCHAR).
 - To ensure that the result is - DATETIME, you can use- CAST()to convert the first argument to- DATETIME.- mysql> SELECT DATE_ADD('2018-05-01',INTERVAL 1 DAY); -> '2018-05-02' mysql> SELECT DATE_SUB('2018-05-01',INTERVAL 1 YEAR); -> '2017-05-01' mysql> SELECT DATE_ADD('2020-12-31 23:59:59', -> INTERVAL 1 SECOND); -> '2021-01-01 00:00:00' mysql> SELECT DATE_ADD('2018-12-31 23:59:59', -> INTERVAL 1 DAY); -> '2019-01-01 23:59:59' mysql> SELECT DATE_ADD('2100-12-31 23:59:59', -> INTERVAL '1:1' MINUTE_SECOND); -> '2101-01-01 00:01:00' mysql> SELECT DATE_SUB('2025-01-01 00:00:00', -> INTERVAL '1 1:1:1' DAY_SECOND); -> '2024-12-30 22:58:59' mysql> SELECT DATE_ADD('1900-01-01 00:00:00', -> INTERVAL '-1 10' DAY_HOUR); -> '1899-12-30 14:00:00' mysql> SELECT DATE_SUB('1998-01-02', INTERVAL 31 DAY); -> '1997-12-02' mysql> SELECT DATE_ADD('1992-12-31 23:59:59.000002', -> INTERVAL '1.999999' SECOND_MICROSECOND); -> '1993-01-01 00:00:01.000001'- When adding a - MONTHinterval to a- DATEor- DATETIMEvalue, and the resulting date includes a day that does not exist in the given month, the day is adjusted to the last day of the month, as shown here:- mysql> SELECT DATE_ADD('2024-03-30', INTERVAL 1 MONTH) AS d1, > DATE_ADD('2024-03-31', INTERVAL 1 MONTH) AS d2; +------------+------------+ | d1 | d2 | +------------+------------+ | 2024-04-30 | 2024-04-30 | +------------+------------+ 1 row in set (0.00 sec)
- Formats the - datevalue according to the- formatstring. If either argument is- NULL, the function returns- NULL.- The specifiers shown in the following table may be used in the - formatstring. The- %character is required before format specifier characters. The specifiers apply to other functions as well:- STR_TO_DATE(),- TIME_FORMAT(),- UNIX_TIMESTAMP().- Specifier - Description - %a- Abbreviated weekday name ( - Sun..- Sat)- %b- Abbreviated month name ( - Jan..- Dec)- %c- Month, numeric ( - 0..- 12)- %D- Day of the month with English suffix ( - 0th,- 1st,- 2nd,- 3rd, …)- %d- Day of the month, numeric ( - 00..- 31)- %e- Day of the month, numeric ( - 0..- 31)- %f- Microseconds ( - 000000..- 999999)- %H- Hour ( - 00..- 23)- %h- Hour ( - 01..- 12)- %I- Hour ( - 01..- 12)- %i- Minutes, numeric ( - 00..- 59)- %j- Day of year ( - 001..- 366)- %k- Hour ( - 0..- 23)- %l- Hour ( - 1..- 12)- %M- Month name ( - January..- December)- %m- Month, numeric ( - 00..- 12)- %p- AMor- PM- %r- Time, 12-hour ( - hh:mm:ssfollowed by- AMor- PM)- %S- Seconds ( - 00..- 59)- %s- Seconds ( - 00..- 59)- %T- Time, 24-hour ( - hh:mm:ss)- %U- Week ( - 00..- 53), where Sunday is the first day of the week;- WEEK()mode 0- %u- Week ( - 00..- 53), where Monday is the first day of the week;- WEEK()mode 1- %V- Week ( - 01..- 53), where Sunday is the first day of the week;- WEEK()mode 2; used with- %X- %v- Week ( - 01..- 53), where Monday is the first day of the week;- WEEK()mode 3; used with- %x- %W- Weekday name ( - Sunday..- Saturday)- %w- Day of the week ( - 0=Sunday..- 6=Saturday)- %X- Year for the week where Sunday is the first day of the week, numeric, four digits; used with - %V- %x- Year for the week, where Monday is the first day of the week, numeric, four digits; used with - %v- %Y- Year, numeric, four digits - %y- Year, numeric (two digits) - %%- A literal - %character- %- x- x, for any “- x” not listed above- Ranges for the month and day specifiers begin with zero due to the fact that MySQL permits the storing of incomplete dates such as - '2014-00-00'.- The language used for day and month names and abbreviations is controlled by the value of the - lc_time_namessystem variable (Section 12.16, “MySQL Server Locale Support”).- For the - %U,- %u,- %V, and- %vspecifiers, see the description of the- WEEK()function for information about the mode values. The mode affects how week numbering occurs.- DATE_FORMAT()returns a string with a character set and collation given by- character_set_connectionand- collation_connectionso that it can return month and weekday names containing non-ASCII characters.- mysql> SELECT DATE_FORMAT('2009-10-04 22:23:00', '%W %M %Y'); -> 'Sunday October 2009' mysql> SELECT DATE_FORMAT('2007-10-04 22:23:00', '%H:%i:%s'); -> '22:23:00' mysql> SELECT DATE_FORMAT('1900-10-04 22:23:00', -> '%D %y %a %d %m %b %j'); -> '4th 00 Thu 04 10 Oct 277' mysql> SELECT DATE_FORMAT('1997-10-04 22:23:00', -> '%H %k %I %r %T %S %w'); -> '22 22 10 10:23:00 PM 22:23:00 00 6' mysql> SELECT DATE_FORMAT('1999-01-01', '%X %V'); -> '1998 52' mysql> SELECT DATE_FORMAT('2006-06-00', '%d'); -> '00'
- DATE_SUB(- date,INTERVAL- expr- unit)- See the description for - DATE_ADD().
- DAY()is a synonym for- DAYOFMONTH().
- Returns the name of the weekday for - date. The language used for the name is controlled by the value of the- lc_time_namessystem variable (see Section 12.16, “MySQL Server Locale Support”). Returns- NULLif- dateis- NULL.- mysql> SELECT DAYNAME('2007-02-03'); -> 'Saturday'
- Returns the day of the month for - date, in the range- 1to- 31, or- 0for dates such as- '0000-00-00'or- '2008-00-00'that have a zero day part. Returns- NULLif- dateis- NULL.- mysql> SELECT DAYOFMONTH('2007-02-03'); -> 3
- Returns the weekday index for - date(- 1= Sunday,- 2= Monday, …,- 7= Saturday). These index values correspond to the ODBC standard. Returns- NULLif- dateis- NULL.- mysql> SELECT DAYOFWEEK('2007-02-03'); -> 7
- Returns the day of the year for - date, in the range- 1to- 366. Returns- NULLif- dateis- NULL.- mysql> SELECT DAYOFYEAR('2007-02-03'); -> 34
- The - EXTRACT()function uses the same kinds of- unitspecifiers as- DATE_ADD()or- DATE_SUB(), but extracts parts from the date rather than performing date arithmetic. For information on the- unitargument, see Temporal Intervals. Returns- NULLif- dateis- NULL.- mysql> SELECT EXTRACT(YEAR FROM '2019-07-02'); -> 2019 mysql> SELECT EXTRACT(YEAR_MONTH FROM '2019-07-02 01:02:03'); -> 201907 mysql> SELECT EXTRACT(DAY_MINUTE FROM '2019-07-02 01:02:03'); -> 20102 mysql> SELECT EXTRACT(MICROSECOND -> FROM '2003-01-02 10:30:00.000123'); -> 123
- Given a day number - N, returns a- DATEvalue. Returns- NULLif- Nis- NULL.- mysql> SELECT FROM_DAYS(730669); -> '2000-07-03'- Use - FROM_DAYS()with caution on old dates. It is not intended for use with values that precede the advent of the Gregorian calendar (1582). See Section 13.2.7, “What Calendar Is Used By MySQL?”.
- FROM_UNIXTIME(- unix_timestamp[,- format])- Returns a representation of - unix_timestampas a datetime or character string value. The value returned is expressed using the session time zone. (Clients can set the session time zone as described in Section 7.1.15, “MySQL Server Time Zone Support”.)- unix_timestampis an internal timestamp value representing seconds since- '1970-01-01 00:00:00'UTC, such as produced by the- UNIX_TIMESTAMP()function.- If - formatis omitted, this function returns a- DATETIMEvalue.- If - unix_timestampor- formatis- NULL, this function returns- NULL.- If - unix_timestampis an integer, the fractional seconds precision of the- DATETIMEis zero. When- unix_timestampis a decimal value, the fractional seconds precision of the- DATETIMEis the same as the precision of the decimal value, up to a maximum of 6. When- unix_timestampis a floating point number, the fractional seconds precision of the datetime is 6.- On 32-bit platforms, the maximum useful value for - unix_timestampis 2147483647.999999, which returns- '2038-01-19 03:14:07.999999'UTC. On 64-bit platforms, the effective maximum is 32536771199.999999, which returns- '3001-01-18 23:59:59.999999'UTC. Regardless of platform or version, a greater value for- unix_timestampthan the effective maximum returns- 0.- formatis used to format the result in the same way as the format string used for the- DATE_FORMAT()function. If- formatis supplied, the value returned is a- VARCHAR.- mysql> SELECT FROM_UNIXTIME(1447430881); -> '2015-11-13 10:08:01' mysql> SELECT FROM_UNIXTIME(1447430881) + 0; -> 20151113100801 mysql> SELECT FROM_UNIXTIME(1447430881, -> '%Y %D %M %h:%i:%s %x'); -> '2015 13th November 10:08:01 2015'Note- If you use - UNIX_TIMESTAMP()and- FROM_UNIXTIME()to convert between values in a non-UTC time zone and Unix timestamp values, the conversion is lossy because the mapping is not one-to-one in both directions. For details, see the description of the- UNIX_TIMESTAMP()function.
- GET_FORMAT({DATE|TIME|DATETIME}, {'EUR'|'USA'|'JIS'|'ISO'|'INTERNAL'})- Returns a format string. This function is useful in combination with the - DATE_FORMAT()and the- STR_TO_DATE()functions.- If - formatis- NULL, this function returns- NULL.- The possible values for the first and second arguments result in several possible format strings (for the specifiers used, see the table in the - DATE_FORMAT()function description). ISO format refers to ISO 9075, not ISO 8601.- Function Call - Result - GET_FORMAT(DATE,'USA')- '%m.%d.%Y'- GET_FORMAT(DATE,'JIS')- '%Y-%m-%d'- GET_FORMAT(DATE,'ISO')- '%Y-%m-%d'- GET_FORMAT(DATE,'EUR')- '%d.%m.%Y'- GET_FORMAT(DATE,'INTERNAL')- '%Y%m%d'- GET_FORMAT(DATETIME,'USA')- '%Y-%m-%d %H.%i.%s'- GET_FORMAT(DATETIME,'JIS')- '%Y-%m-%d %H:%i:%s'- GET_FORMAT(DATETIME,'ISO')- '%Y-%m-%d %H:%i:%s'- GET_FORMAT(DATETIME,'EUR')- '%Y-%m-%d %H.%i.%s'- GET_FORMAT(DATETIME,'INTERNAL')- '%Y%m%d%H%i%s'- GET_FORMAT(TIME,'USA')- '%h:%i:%s %p'- GET_FORMAT(TIME,'JIS')- '%H:%i:%s'- GET_FORMAT(TIME,'ISO')- '%H:%i:%s'- GET_FORMAT(TIME,'EUR')- '%H.%i.%s'- GET_FORMAT(TIME,'INTERNAL')- '%H%i%s'- TIMESTAMPcan also be used as the first argument to- GET_FORMAT(), in which case the function returns the same values as for- DATETIME.- mysql> SELECT DATE_FORMAT('2003-10-03',GET_FORMAT(DATE,'EUR')); -> '03.10.2003' mysql> SELECT STR_TO_DATE('10.31.2003',GET_FORMAT(DATE,'USA')); -> '2003-10-31'
- Returns the hour for - time. The range of the return value is- 0to- 23for time-of-day values. However, the range of- TIMEvalues actually is much larger, so- HOURcan return values greater than- 23. Returns- NULLif- timeis- NULL.- mysql> SELECT HOUR('10:05:03'); -> 10 mysql> SELECT HOUR('272:59:59'); -> 272
- Takes a date or datetime value and returns the corresponding value for the last day of the month. Returns - NULLif the argument is invalid or- NULL.- mysql> SELECT LAST_DAY('2003-02-05'); -> '2003-02-28' mysql> SELECT LAST_DAY('2004-02-05'); -> '2004-02-29' mysql> SELECT LAST_DAY('2004-01-01 01:01:01'); -> '2004-01-31' mysql> SELECT LAST_DAY('2003-03-32'); -> NULL
- LOCALTIMEand- LOCALTIME()are synonyms for- NOW().
- LOCALTIMESTAMP,- LOCALTIMESTAMP([- fsp])- LOCALTIMESTAMPand- LOCALTIMESTAMP()are synonyms for- NOW().
- Returns a date, given year and day-of-year values. - dayofyearmust be greater than 0 or the result is- NULL. The result is also- NULLif either argument is- NULL.- mysql> SELECT MAKEDATE(2011,31), MAKEDATE(2011,32); -> '2011-01-31', '2011-02-01' mysql> SELECT MAKEDATE(2011,365), MAKEDATE(2014,365); -> '2011-12-31', '2014-12-31' mysql> SELECT MAKEDATE(2011,0); -> NULL
- Returns a time value calculated from the - hour,- minute, and- secondarguments. Returns- NULLif any of its arguments are- NULL.- The - secondargument can have a fractional part.- mysql> SELECT MAKETIME(12,15,30); -> '12:15:30'
- Returns the microseconds from the time or datetime expression - expras a number in the range from- 0to- 999999. Returns- NULLif- expris- NULL.- mysql> SELECT MICROSECOND('12:00:00.123456'); -> 123456 mysql> SELECT MICROSECOND('2019-12-31 23:59:59.000010'); -> 10
- Returns the minute for - time, in the range- 0to- 59, or- NULLif- timeis- NULL.- mysql> SELECT MINUTE('2008-02-03 10:05:03'); -> 5
- Returns the month for - date, in the range- 1to- 12for January to December, or- 0for dates such as- '0000-00-00'or- '2008-00-00'that have a zero month part. Returns- NULLif- dateis- NULL.- mysql> SELECT MONTH('2008-02-03'); -> 2
- Returns the full name of the month for - date. The language used for the name is controlled by the value of the- lc_time_namessystem variable (Section 12.16, “MySQL Server Locale Support”). Returns- NULLif- dateis- NULL.- mysql> SELECT MONTHNAME('2008-02-03'); -> 'February'
- Returns the current date and time as a value in - 'or- YYYY-MM-DD hh:mm:ss'- YYYYMMDDhhmmssformat, depending on whether the function is used in string or numeric context. The value is expressed in the session time zone.- If the - fspargument is given to specify a fractional seconds precision from 0 to 6, the return value includes a fractional seconds part of that many digits.- mysql> SELECT NOW(); -> '2007-12-15 23:50:26' mysql> SELECT NOW() + 0; -> 20071215235026.000000- NOW()returns a constant time that indicates the time at which the statement began to execute. (Within a stored function or trigger,- NOW()returns the time at which the function or triggering statement began to execute.) This differs from the behavior for- SYSDATE(), which returns the exact time at which it executes.- mysql> SELECT NOW(), SLEEP(2), NOW(); +---------------------+----------+---------------------+ | NOW() | SLEEP(2) | NOW() | +---------------------+----------+---------------------+ | 2006-04-12 13:47:36 | 0 | 2006-04-12 13:47:36 | +---------------------+----------+---------------------+ mysql> SELECT SYSDATE(), SLEEP(2), SYSDATE(); +---------------------+----------+---------------------+ | SYSDATE() | SLEEP(2) | SYSDATE() | +---------------------+----------+---------------------+ | 2006-04-12 13:47:44 | 0 | 2006-04-12 13:47:46 | +---------------------+----------+---------------------+- In addition, the - SET TIMESTAMPstatement affects the value returned by- NOW()but not by- SYSDATE(). This means that timestamp settings in the binary log have no effect on invocations of- SYSDATE(). Setting the timestamp to a nonzero value causes each subsequent invocation of- NOW()to return that value. Setting the timestamp to zero cancels this effect so that- NOW()once again returns the current date and time.- See the description for - SYSDATE()for additional information about the differences between the two functions.
- Adds - Nmonths to period- P(in the format- YYMMor- YYYYMM). Returns a value in the format- YYYYMM.Note- The period argument - Pis not a date value.- This function returns - NULLif- Por- Nis- NULL.- mysql> SELECT PERIOD_ADD(200801,2); -> 200803
- Returns the number of months between periods - P1and- P2.- P1and- P2should be in the format- YYMMor- YYYYMM. Note that the period arguments- P1and- P2are not date values.- This function returns - NULLif- P1or- P2is- NULL.- mysql> SELECT PERIOD_DIFF(200802,200703); -> 11
- Returns the quarter of the year for - date, in the range- 1to- 4, or- NULLif- dateis- NULL.- mysql> SELECT QUARTER('2008-04-01'); -> 2
- Returns the second for - time, in the range- 0to- 59, or- NULLif- timeis- NULL.- mysql> SELECT SECOND('10:05:03'); -> 3
- Returns the - secondsargument, converted to hours, minutes, and seconds, as a- TIMEvalue. The range of the result is constrained to that of the- TIMEdata type. A warning occurs if the argument corresponds to a value outside that range.- The function returns - NULLif- secondsis- NULL.- mysql> SELECT SEC_TO_TIME(2378); -> '00:39:38' mysql> SELECT SEC_TO_TIME(2378) + 0; -> 3938
- This is the inverse of the - DATE_FORMAT()function. It takes a string- strand a format string- format.- STR_TO_DATE()returns a- DATETIMEvalue if the format string contains both date and time parts, or a- DATEor- TIMEvalue if the string contains only date or time parts. If- stror- formatis- NULL, the function returns- NULL. If the date, time, or datetime value extracted from- strcannot be parsed according to the rules followed by the server,- STR_TO_DATE()returns- NULLand produces a warning.- The server scans - strattempting to match- formatto it. The format string can contain literal characters and format specifiers beginning with- %. Literal characters in- formatmust match literally in- str. Format specifiers in- formatmust match a date or time part in- str. For the specifiers that can be used in- format, see the- DATE_FORMAT()function description.- mysql> SELECT STR_TO_DATE('01,5,2013','%d,%m,%Y'); -> '2013-05-01' mysql> SELECT STR_TO_DATE('May 1, 2013','%M %d,%Y'); -> '2013-05-01'- Scanning starts at the beginning of - strand fails if- formatis found not to match. Extra characters at the end of- strare ignored.- mysql> SELECT STR_TO_DATE('a09:30:17','a%h:%i:%s'); -> '09:30:17' mysql> SELECT STR_TO_DATE('a09:30:17','%h:%i:%s'); -> NULL mysql> SELECT STR_TO_DATE('09:30:17a','%h:%i:%s'); -> '09:30:17'- Unspecified date or time parts have a value of 0, so incompletely specified values in - strproduce a result with some or all parts set to 0:- mysql> SELECT STR_TO_DATE('abc','abc'); -> '0000-00-00' mysql> SELECT STR_TO_DATE('9','%m'); -> '0000-09-00' mysql> SELECT STR_TO_DATE('9','%s'); -> '00:00:09'- Range checking on the parts of date values is as described in Section 13.2.2, “The DATE, DATETIME, and TIMESTAMP Types”. This means, for example, that “zero” dates or dates with part values of 0 are permitted unless the SQL mode is set to disallow such values. - mysql> SELECT STR_TO_DATE('00/00/0000', '%m/%d/%Y'); -> '0000-00-00' mysql> SELECT STR_TO_DATE('04/31/2004', '%m/%d/%Y'); -> '2004-04-31'- If the - NO_ZERO_DATESQL mode is enabled, zero dates are disallowed. In that case,- STR_TO_DATE()returns- NULLand generates a warning:- mysql> SET sql_mode = ''; mysql> SELECT STR_TO_DATE('00/00/0000', '%m/%d/%Y'); +---------------------------------------+ | STR_TO_DATE('00/00/0000', '%m/%d/%Y') | +---------------------------------------+ | 0000-00-00 | +---------------------------------------+ mysql> SET sql_mode = 'NO_ZERO_DATE'; mysql> SELECT STR_TO_DATE('00/00/0000', '%m/%d/%Y'); +---------------------------------------+ | STR_TO_DATE('00/00/0000', '%m/%d/%Y') | +---------------------------------------+ | NULL | +---------------------------------------+ mysql> SHOW WARNINGS\G *************************** 1. row *************************** Level: Warning Code: 1411 Message: Incorrect datetime value: '00/00/0000' for function str_to_date- In some previous versions of MySQL, it was possible to pass an invalid date string such as - '2021-11-31'to this function. In MySQL 8.4,- STR_TO_DATE()performs complete range checking and raises an error if the date after conversion would be invalid.Note- You cannot use format - "%X%V"to convert a year-week string to a date because the combination of a year and week does not uniquely identify a year and month if the week crosses a month boundary. To convert a year-week to a date, you should also specify the weekday:- mysql> SELECT STR_TO_DATE('200442 Monday', '%X%V %W'); -> '2004-10-18'- You should also be aware that, for dates and the date portions of datetime values, - STR_TO_DATE()checks (only) the individual year, month, and day of month values for validity. More precisely, this means that the year is checked to be sure that it is in the range 0-9999 inclusive, the month is checked to ensure that it is in the range 1-12 inclusive, and the day of month is checked to make sure that it is in the range 1-31 inclusive, but the server does not check the values in combination. For example,- SELECT STR_TO_DATE('23-2-31', '%Y-%m-%d')returns- 2023-02-31. Enabling or disabling the- ALLOW_INVALID_DATESserver SQL mode has no effect on this behavior. See Section 13.2.2, “The DATE, DATETIME, and TIMESTAMP Types”, for more information.
- SUBDATE(,- date,INTERVAL- expr- unit)- SUBDATE(- expr,- days)- When invoked with the - INTERVALform of the second argument,- SUBDATE()is a synonym for- DATE_SUB(). For information on the- INTERVAL- unitargument, see the discussion for- DATE_ADD().- mysql> SELECT DATE_SUB('2008-01-02', INTERVAL 31 DAY); -> '2007-12-02' mysql> SELECT SUBDATE('2008-01-02', INTERVAL 31 DAY); -> '2007-12-02'- The second form enables the use of an integer value for - days. In such cases, it is interpreted as the number of days to be subtracted from the date or datetime expression- expr.- mysql> SELECT SUBDATE('2008-01-02 12:00:00', 31); -> '2007-12-02 12:00:00'- This function returns - NULLif any of its arguments are- NULL.
- SUBTIME()returns- expr1−- expr2expressed as a value in the same format as- expr1.- expr1is a time or datetime expression, and- expr2is a time expression.- Resolution of this function's return type is performed as it is for the - ADDTIME()function; see the description of that function for more information.- mysql> SELECT SUBTIME('2007-12-31 23:59:59.999999','1 1:1:1.000002'); -> '2007-12-30 22:58:58.999997' mysql> SELECT SUBTIME('01:00:00.999999', '02:00:00.999998'); -> '-00:59:59.999999'- This function returns - NULLif- expr1or- expr2is- NULL.
- Returns the current date and time as a value in - 'or- YYYY-MM-DD hh:mm:ss'- YYYYMMDDhhmmssformat, depending on whether the function is used in string or numeric context.- If the - fspargument is given to specify a fractional seconds precision from 0 to 6, the return value includes a fractional seconds part of that many digits.- SYSDATE()returns the time at which it executes. This differs from the behavior for- NOW(), which returns a constant time that indicates the time at which the statement began to execute. (Within a stored function or trigger,- NOW()returns the time at which the function or triggering statement began to execute.)- mysql> SELECT NOW(), SLEEP(2), NOW(); +---------------------+----------+---------------------+ | NOW() | SLEEP(2) | NOW() | +---------------------+----------+---------------------+ | 2006-04-12 13:47:36 | 0 | 2006-04-12 13:47:36 | +---------------------+----------+---------------------+ mysql> SELECT SYSDATE(), SLEEP(2), SYSDATE(); +---------------------+----------+---------------------+ | SYSDATE() | SLEEP(2) | SYSDATE() | +---------------------+----------+---------------------+ | 2006-04-12 13:47:44 | 0 | 2006-04-12 13:47:46 | +---------------------+----------+---------------------+- In addition, the - SET TIMESTAMPstatement affects the value returned by- NOW()but not by- SYSDATE(). This means that timestamp settings in the binary log have no effect on invocations of- SYSDATE().- Because - SYSDATE()can return different values even within the same statement, and is not affected by- SET TIMESTAMP, it is nondeterministic and therefore unsafe for replication if statement-based binary logging is used. If that is a problem, you can use row-based logging.- Alternatively, you can use the - --sysdate-is-nowoption to cause- SYSDATE()to be an alias for- NOW(). This works if the option is used on both the replication source server and the replica.- The nondeterministic nature of - SYSDATE()also means that indexes cannot be used for evaluating expressions that refer to it.
- Extracts the time part of the time or datetime expression - exprand returns it as a string. Returns- NULLif- expris- NULL.- This function is unsafe for statement-based replication. A warning is logged if you use this function when - binlog_formatis set to- STATEMENT.- mysql> SELECT TIME('2003-12-31 01:02:03'); -> '01:02:03' mysql> SELECT TIME('2003-12-31 01:02:03.000123'); -> '01:02:03.000123'
- TIMEDIFF()returns- expr1−- expr2expressed as a time value.- expr1and- expr2are strings which are converted to- TIMEor- DATETIMEexpressions; these must be of the same type following conversion. Returns- NULLif- expr1or- expr2is- NULL.- The result returned by - TIMEDIFF()is limited to the range allowed for- TIMEvalues. Alternatively, you can use either of the functions- TIMESTAMPDIFF()and- UNIX_TIMESTAMP(), both of which return integers.- mysql> SELECT TIMEDIFF('2000-01-01 00:00:00', -> '2000-01-01 00:00:00.000001'); -> '-00:00:00.000001' mysql> SELECT TIMEDIFF('2008-12-31 23:59:59.000001', -> '2008-12-30 01:01:01.000002'); -> '46:58:57.999999'
- TIMESTAMP(,- expr)- TIMESTAMP(- expr1,- expr2)- With a single argument, this function returns the date or datetime expression - expras a datetime value. With two arguments, it adds the time expression- expr2to the date or datetime expression- expr1and returns the result as a datetime value. Returns- NULLif- expr,- expr1, or- expr2is- NULL.- mysql> SELECT TIMESTAMP('2003-12-31'); -> '2003-12-31 00:00:00' mysql> SELECT TIMESTAMP('2003-12-31 12:00:00','12:00:00'); -> '2004-01-01 00:00:00'
- TIMESTAMPADD(- unit,- interval,- datetime_expr)- Adds the integer expression - intervalto the date or datetime expression- datetime_expr. The unit for- intervalis given by the- unitargument, which should be one of the following values:- MICROSECOND(microseconds),- SECOND,- MINUTE,- HOUR,- DAY,- WEEK,- MONTH,- QUARTER, or- YEAR.- The - unitvalue may be specified using one of keywords as shown, or with a prefix of- SQL_TSI_. For example,- DAYand- SQL_TSI_DAYboth are legal.- This function returns - NULLif- intervalor- datetime_expris- NULL.- mysql> SELECT TIMESTAMPADD(MINUTE, 1, '2003-01-02'); -> '2003-01-02 00:01:00' mysql> SELECT TIMESTAMPADD(WEEK,1,'2003-01-02'); -> '2003-01-09'- When adding a - MONTHinterval to a- DATEor- DATETIMEvalue, and the resulting date includes a day that does not exist in the given month, the day is adjusted to the last day of the month, as shown here:- mysql> SELECT TIMESTAMPADD(MONTH, 1, DATE '2024-03-30') AS t1, > TIMESTAMPADD(MONTH, 1, DATE '2024-03-31') AS t2; +------------+------------+ | t1 | t2 | +------------+------------+ | 2024-04-30 | 2024-04-30 | +------------+------------+ 1 row in set (0.00 sec)
- TIMESTAMPDIFF(- unit,- datetime_expr1,- datetime_expr2)- Returns - datetime_expr2−- datetime_expr1, where- datetime_expr1and- datetime_expr2are date or datetime expressions. One expression may be a date and the other a datetime; a date value is treated as a datetime having the time part- '00:00:00'where necessary. The unit for the result (an integer) is given by the- unitargument. The legal values for- unitare the same as those listed in the description of the- TIMESTAMPADD()function.- This function returns - NULLif- datetime_expr1or- datetime_expr2is- NULL.- mysql> SELECT TIMESTAMPDIFF(MONTH,'2003-02-01','2003-05-01'); -> 3 mysql> SELECT TIMESTAMPDIFF(YEAR,'2002-05-01','2001-01-01'); -> -1 mysql> SELECT TIMESTAMPDIFF(MINUTE,'2003-02-01','2003-05-01 12:05:55'); -> 128885Note- The order of the date or datetime arguments for this function is the opposite of that used with the - TIMESTAMP()function when invoked with 2 arguments.
- This is used like the - DATE_FORMAT()function, but the- formatstring may contain format specifiers only for hours, minutes, seconds, and microseconds. Other specifiers produce a- NULLor- 0.- TIME_FORMAT()returns- NULLif- timeor- formatis- NULL.- If the - timevalue contains an hour part that is greater than- 23, the- %Hand- %khour format specifiers produce a value larger than the usual range of- 0..23. The other hour format specifiers produce the hour value modulo 12.- mysql> SELECT TIME_FORMAT('100:00:00', '%H %k %h %I %l'); -> '100 100 04 04 4'
- Returns the - timeargument, converted to seconds. Returns- NULLif- timeis- NULL.- mysql> SELECT TIME_TO_SEC('22:23:00'); -> 80580 mysql> SELECT TIME_TO_SEC('00:39:38'); -> 2378
- Given a date - date, returns a day number (the number of days since year 0). Returns- NULLif- dateis- NULL.- mysql> SELECT TO_DAYS(950501); -> 728779 mysql> SELECT TO_DAYS('2007-10-07'); -> 733321- TO_DAYS()is not intended for use with values that precede the advent of the Gregorian calendar (1582), because it does not take into account the days that were lost when the calendar was changed. For dates before 1582 (and possibly a later year in other locales), results from this function are not reliable. See Section 13.2.7, “What Calendar Is Used By MySQL?”, for details.- Remember that MySQL converts two-digit year values in dates to four-digit form using the rules in Section 13.2, “Date and Time Data Types”. For example, - '2008-10-07'and- '08-10-07'are seen as identical dates:- mysql> SELECT TO_DAYS('2008-10-07'), TO_DAYS('08-10-07'); -> 733687, 733687- In MySQL, the zero date is defined as - '0000-00-00', even though this date is itself considered invalid. This means that, for- '0000-00-00'and- '0000-01-01',- TO_DAYS()returns the values shown here:- mysql> SELECT TO_DAYS('0000-00-00'); +-----------------------+ | to_days('0000-00-00') | +-----------------------+ | NULL | +-----------------------+ 1 row in set, 1 warning (0.00 sec) mysql> SHOW WARNINGS; +---------+------+----------------------------------------+ | Level | Code | Message | +---------+------+----------------------------------------+ | Warning | 1292 | Incorrect datetime value: '0000-00-00' | +---------+------+----------------------------------------+ 1 row in set (0.00 sec) mysql> SELECT TO_DAYS('0000-01-01'); +-----------------------+ | to_days('0000-01-01') | +-----------------------+ | 1 | +-----------------------+ 1 row in set (0.00 sec)- This is true whether or not the - ALLOW_INVALID_DATESSQL server mode is enabled.
- Given a date or datetime - expr, returns the number of seconds since the year 0. If- expris not a valid date or datetime value (including- NULL), it returns- NULL.- mysql> SELECT TO_SECONDS(950501); -> 62966505600 mysql> SELECT TO_SECONDS('2009-11-29'); -> 63426672000 mysql> SELECT TO_SECONDS('2009-11-29 13:43:32'); -> 63426721412 mysql> SELECT TO_SECONDS( NOW() ); -> 63426721458- Like - TO_DAYS(),- TO_SECONDS()is not intended for use with values that precede the advent of the Gregorian calendar (1582), because it does not take into account the days that were lost when the calendar was changed. For dates before 1582 (and possibly a later year in other locales), results from this function are not reliable. See Section 13.2.7, “What Calendar Is Used By MySQL?”, for details.- Like - TO_DAYS(),- TO_SECONDS(), converts two-digit year values in dates to four-digit form using the rules in Section 13.2, “Date and Time Data Types”.- In MySQL, the zero date is defined as - '0000-00-00', even though this date is itself considered invalid. This means that, for- '0000-00-00'and- '0000-01-01',- TO_SECONDS()returns the values shown here:- mysql> SELECT TO_SECONDS('0000-00-00'); +--------------------------+ | TO_SECONDS('0000-00-00') | +--------------------------+ | NULL | +--------------------------+ 1 row in set, 1 warning (0.00 sec) mysql> SHOW WARNINGS; +---------+------+----------------------------------------+ | Level | Code | Message | +---------+------+----------------------------------------+ | Warning | 1292 | Incorrect datetime value: '0000-00-00' | +---------+------+----------------------------------------+ 1 row in set (0.00 sec) mysql> SELECT TO_SECONDS('0000-01-01'); +--------------------------+ | TO_SECONDS('0000-01-01') | +--------------------------+ | 86400 | +--------------------------+ 1 row in set (0.00 sec)- This is true whether or not the - ALLOW_INVALID_DATESSQL server mode is enabled.
- If - UNIX_TIMESTAMP()is called with no- dateargument, it returns a Unix timestamp representing seconds since- '1970-01-01 00:00:00'UTC.- If - UNIX_TIMESTAMP()is called with a- dateargument, it returns the value of the argument as seconds since- '1970-01-01 00:00:00'UTC. The server interprets- dateas a value in the session time zone and converts it to an internal Unix timestamp value in UTC. (Clients can set the session time zone as described in Section 7.1.15, “MySQL Server Time Zone Support”.) The- dateargument may be a- DATE,- DATETIME, or- TIMESTAMPstring, or a number in- YYMMDD,- YYMMDDhhmmss,- YYYYMMDD, or- YYYYMMDDhhmmssformat. If the argument includes a time part, it may optionally include a fractional seconds part.- The return value is an integer if no argument is given or the argument does not include a fractional seconds part, or - DECIMALif an argument is given that includes a fractional seconds part.- When the - dateargument is a- TIMESTAMPcolumn,- UNIX_TIMESTAMP()returns the internal timestamp value directly, with no implicit “string-to-Unix-timestamp” conversion.- The valid range of argument values is the same as for the - TIMESTAMPdata type:- '1970-01-01 00:00:01.000000'UTC to- '2038-01-19 03:14:07.999999'UTC for 32-bit platforms; for MySQL running on 64-bit platforms, the valid range of argument values for- UNIX_TIMESTAMP()is- '1970-01-01 00:00:01.000000'UTC to- '3001-01-19 03:14:07.999999'UTC (corresponding to 32536771199.999999 seconds).- Regardless of MySQL version or platform architecture, if you pass an out-of-range date to - UNIX_TIMESTAMP(), it returns- 0. If- dateis- NULL, it returns- NULL.- mysql> SELECT UNIX_TIMESTAMP(); -> 1447431666 mysql> SELECT UNIX_TIMESTAMP('2015-11-13 10:20:19'); -> 1447431619 mysql> SELECT UNIX_TIMESTAMP('2015-11-13 10:20:19.012'); -> 1447431619.012- If you use - UNIX_TIMESTAMP()and- FROM_UNIXTIME()to convert between values in a non-UTC time zone and Unix timestamp values, the conversion is lossy because the mapping is not one-to-one in both directions. For example, due to conventions for local time zone changes such as Daylight Saving Time (DST), it is possible for- UNIX_TIMESTAMP()to map two values that are distinct in a non-UTC time zone to the same Unix timestamp value.- FROM_UNIXTIME()maps that value back to only one of the original values. Here is an example, using values that are distinct in the- METtime zone:- mysql> SET time_zone = 'MET'; mysql> SELECT UNIX_TIMESTAMP('2005-03-27 03:00:00'); +---------------------------------------+ | UNIX_TIMESTAMP('2005-03-27 03:00:00') | +---------------------------------------+ | 1111885200 | +---------------------------------------+ mysql> SELECT UNIX_TIMESTAMP('2005-03-27 02:00:00'); +---------------------------------------+ | UNIX_TIMESTAMP('2005-03-27 02:00:00') | +---------------------------------------+ | 1111885200 | +---------------------------------------+ mysql> SELECT FROM_UNIXTIME(1111885200); +---------------------------+ | FROM_UNIXTIME(1111885200) | +---------------------------+ | 2005-03-27 03:00:00 | +---------------------------+Note- To use named time zones such as - 'MET'or- 'Europe/Amsterdam', the time zone tables must be properly set up. For instructions, see Section 7.1.15, “MySQL Server Time Zone Support”.- If you want to subtract - UNIX_TIMESTAMP()columns, you might want to cast them to signed integers. See Section 14.10, “Cast Functions and Operators”.
- Returns the current UTC date as a value in - 'or- YYYY-MM-DD'- YYYYMMDDformat, depending on whether the function is used in string or numeric context.- mysql> SELECT UTC_DATE(), UTC_DATE() + 0; -> '2003-08-14', 20030814
- Returns the current UTC time as a value in - 'hh:mm:ss'or- hhmmssformat, depending on whether the function is used in string or numeric context.- If the - fspargument is given to specify a fractional seconds precision from 0 to 6, the return value includes a fractional seconds part of that many digits.- mysql> SELECT UTC_TIME(), UTC_TIME() + 0; -> '18:07:53', 180753.000000
- UTC_TIMESTAMP,- UTC_TIMESTAMP([- fsp])- Returns the current UTC date and time as a value in - 'or- YYYY-MM-DD hh:mm:ss'- YYYYMMDDhhmmssformat, depending on whether the function is used in string or numeric context.- If the - fspargument is given to specify a fractional seconds precision from 0 to 6, the return value includes a fractional seconds part of that many digits.- mysql> SELECT UTC_TIMESTAMP(), UTC_TIMESTAMP() + 0; -> '2003-08-14 18:08:04', 20030814180804.000000
- This function returns the week number for - date. The two-argument form of- WEEK()enables you to specify whether the week starts on Sunday or Monday and whether the return value should be in the range from- 0to- 53or from- 1to- 53. If the- modeargument is omitted, the value of the- default_week_formatsystem variable is used. See Section 7.1.8, “Server System Variables”. For a- NULLdate value, the function returns- NULL.- The following table describes how the - modeargument works.- Mode - First day of week - Range - Week 1 is the first week … - 0 - Sunday - 0-53 - with a Sunday in this year - 1 - Monday - 0-53 - with 4 or more days this year - 2 - Sunday - 1-53 - with a Sunday in this year - 3 - Monday - 1-53 - with 4 or more days this year - 4 - Sunday - 0-53 - with 4 or more days this year - 5 - Monday - 0-53 - with a Monday in this year - 6 - Sunday - 1-53 - with 4 or more days this year - 7 - Monday - 1-53 - with a Monday in this year - For - modevalues with a meaning of “with 4 or more days this year,” weeks are numbered according to ISO 8601:1988:- If the week containing January 1 has 4 or more days in the new year, it is week 1. 
- Otherwise, it is the last week of the previous year, and the next week is week 1. 
 - mysql> SELECT WEEK('2008-02-20'); -> 7 mysql> SELECT WEEK('2008-02-20',0); -> 7 mysql> SELECT WEEK('2008-02-20',1); -> 8 mysql> SELECT WEEK('2008-12-31',1); -> 53- If a date falls in the last week of the previous year, MySQL returns - 0if you do not use- 2,- 3,- 6, or- 7as the optional- modeargument:- mysql> SELECT YEAR('2000-01-01'), WEEK('2000-01-01',0); -> 2000, 0- One might argue that - WEEK()should return- 52because the given date actually occurs in the 52nd week of 1999.- WEEK()returns- 0instead so that the return value is “the week number in the given year.” This makes use of the- WEEK()function reliable when combined with other functions that extract a date part from a date.- If you prefer a result evaluated with respect to the year that contains the first day of the week for the given date, use - 0,- 2,- 5, or- 7as the optional- modeargument.- mysql> SELECT WEEK('2000-01-01',2); -> 52- Alternatively, use the - YEARWEEK()function:- mysql> SELECT YEARWEEK('2000-01-01'); -> 199952 mysql> SELECT MID(YEARWEEK('2000-01-01'),5,2); -> '52'
- Returns the weekday index for - date(- 0= Monday,- 1= Tuesday, …- 6= Sunday). Returns- NULLif- dateis- NULL.- mysql> SELECT WEEKDAY('2008-02-03 22:23:00'); -> 6 mysql> SELECT WEEKDAY('2007-11-06'); -> 1
- Returns the calendar week of the date as a number in the range from - 1to- 53. Returns- NULLif- dateis- NULL.- WEEKOFYEAR()is a compatibility function that is equivalent to- WEEK(.- date,3)- mysql> SELECT WEEKOFYEAR('2008-02-20'); -> 8
- Returns the year for - date, in the range- 1000to- 9999, or- 0for the “zero” date. Returns- NULLif- dateis- NULL.- mysql> SELECT YEAR('1987-01-01'); -> 1987
- YEARWEEK(,- date)- YEARWEEK(- date,- mode)- Returns year and week for a date. The year in the result may be different from the year in the date argument for the first and the last week of the year. Returns - NULLif- dateis- NULL.- The - modeargument works exactly like the- modeargument to- WEEK(). For the single-argument syntax, a- modevalue of 0 is used. Unlike- WEEK(), the value of- default_week_formatdoes not influence- YEARWEEK().- mysql> SELECT YEARWEEK('1987-01-01'); -> 198652- The week number is different from what the - WEEK()function would return (- 0) for optional arguments- 0or- 1, as- WEEK()then returns the week in the context of the given year.