Chapter 94. Date and Time Functions

This section describes the functions that can be used to manipulate temporal values. See Date and time 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.

Here is an example that uses date functions. The following query selects all records with a date_col value from within the last 30 days:

mysql> SELECT something FROM tbl_name
           WHERE TO_DAYS(NOW()) - TO_DAYS(date_col) <= 30;

(Note that the query will also select records with dates that lie in the future.)

Functions that expect date values usually will accept datetime values and ignore the time part. Functions that expect time values usually will 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 will always produce the same result. This principle also applies to CURDATE(), CURTIME(), UTC_DATE(), UTC_TIME(), UTC_TIMESTAMP(), and any of their synonyms.

The return value ranges in the following function descriptions apply for complete dates. If a date is a ``zero'' value or an incomplete date such as '2001-11-00', functions that extract a part of a date may return 0. For example, DAYOFMONTH('2001-11-00') returns 0.

ADDDATE(date,INTERVAL expr type) , ADDDATE(expr,days) When invoked with the INTERVAL form of the second argument, ADDDATE() is a synonym for DATE_ADD(). The related function SUBDATE() is a synonym for DATE_SUB().
    mysql> SELECT DATE_ADD('1998-01-02', INTERVAL 31 DAY);
            -> '1998-02-02'
    mysql> SELECT ADDDATE('1998-01-02', INTERVAL 31 DAY);
            -> '1998-02-02'
    
As of MySQL 4.1.1, the second syntax is allowed, where expr is a date or datetime expression and days is the number of days to be added to expr.
    mysql> SELECT ADDDATE('1998-01-02', 31);
            -> '1998-02-02'
    
ADDTIME(expr,expr2)ADDTIME() adds expr2 to expr and returns the result. expr is a date or datetime expression, and expr2 is a time expression.
    mysql> SELECT ADDTIME("1997-12-31 23:59:59.999999", "1 1:1:1.000002");
            -> '1998-01-02 01:01:01.000001'
    mysql> SELECT ADDTIME("01:00:00.999999", "02:00:00.999998");
            -> '03:00:01.999997'
    
ADDTIME() was added in MySQL 4.1.1.
CURDATE() Returns the current date as a value in 'YYYY-MM-DD' or YYYYMMDD format, depending on whether the function is used in a string or numeric context:
    mysql> SELECT CURDATE();
            -> '1997-12-15'
    mysql> SELECT CURDATE() + 0;
            -> 19971215
    
CURRENT_DATE , CURRENT_DATE()CURRENT_DATE and CURRENT_DATE() are synonyms for CURDATE().
CURTIME() Returns the current time as a value in 'HH:MM:SS' or HHMMSS format, depending on whether the function is used in a string or numeric context:
    mysql> SELECT CURTIME();
            -> '23:50:26'
    mysql> SELECT CURTIME() + 0;
            -> 235026
    
CURRENT_TIME , CURRENT_TIME()CURRENT_TIME and CURRENT_TIME() are synonyms for CURTIME().
CURRENT_TIMESTAMP , CURRENT_TIMESTAMP()CURRENT_TIMESTAMP and CURRENT_TIMESTAMP() are synonyms for NOW().
DATE(expr) Extracts the date part of the date or datetime expression expr.
    mysql> SELECT DATE('2003-12-31 01:02:03');
            -> '2003-12-31'
    
DATE() is available as of MySQL 4.1.1.
DATEDIFF(expr,expr2)DATEDIFF() returns the number of days between the start date expr and the end date expr2. expr and expr2 are date or date-and-time expressions. Only the date parts of the values are used in the calculation.
    mysql> SELECT DATEDIFF('1997-12-31 23:59:59','1997-12-30');
            -> 1
    mysql> SELECT DATEDIFF('1997-11-31 23:59:59','1997-12-31');
            -> -30
    
DATEDIFF() was added in MySQL 4.1.1.
DATE_ADD(date,INTERVAL expr type) , DATE_SUB(date,INTERVAL expr type) These functions perform date arithmetic. As of MySQL Version 3.23, INTERVAL expr type is allowed on either side of the + operator if the expression on the other side is a date or datetime value. For the - operator, INTERVAL expr type is allowed only on the right side, because it makes no sense to subtract a date or datetime value from an interval. (See examples below.) date is a DATETIME or DATE value specifying the starting date. expr is an expression specifying the interval value to be added or subtracted from the starting date. expr is a string; it may start with a - for negative intervals. type is a keyword indicating how the expression should be interpreted. The following table shows how the type and expr arguments are related:
typeValueExpectedexprFormat
MICROSECONDMICROSECONDS
SECONDSECONDS
MINUTEMINUTES
HOURHOURS
DAYDAYS
WEEKWEEKS
MONTHMONTHS
QUARTERQUARTERS
YEARYEARS
SECOND_MICROSECOND'SECONDS.MICROSECONDS'
MINUTE_MICROSECOND'MINUTES.MICROSECONDS'
MINUTE_SECOND'MINUTES:SECONDS'
HOUR_MICROSECOND'HOURS.MICROSECONDS'
HOUR_SECOND'HOURS:MINUTES:SECONDS'
HOUR_MINUTE'HOURS:MINUTES'
DAY_MICROSECOND'DAYS.MICROSECONDS'
DAY_SECOND'DAYS HOURS:MINUTES:SECONDS'
DAY_MINUTE'DAYS HOURS:MINUTES'
DAY_HOUR'DAYS HOURS'
YEAR_MONTH'YEARS-MONTHS'
DATE_FORMAT(date,format) Formats the date value according to the format string. The following specifiers may be used in the format string:
SpecifierDescription
%aAbbreviated weekday name (Sun..Sat)
%bAbbreviated month name (Jan..Dec)
%cMonth, numeric (0..12)
%DDay of the month with English suffix (0th, 1st, 2nd, 3rd, etc.)
%dDay of the month, numeric (00..31)
%eDay of the month, numeric (0..31)
%fMicroseconds (000000..999999)
%HHour (00..23)
%hHour (01..12)
%IHour (01..12)
%iMinutes, numeric (00..59)
%jDay of year (001..366)
%kHour (0..23)
%lHour (1..12)
%MMonth name (January..December)
%mMonth, numeric (00..12)
%pAM or PM
%rTime, 12-hour (hh:mm:ss followed by AM or PM)
%SSeconds (00..59)
%sSeconds (00..59)
%TTime, 24-hour (hh:mm:ss)
%UWeek (00..53), where Sunday is the first day of the week
%uWeek (00..53), where Monday is the first day of the week
%VWeek (01..53), where Sunday is the first day of the week; used with %X
%vWeek (01..53), where Monday is the first day of the week; used with %x
%WWeekday name (Sunday..Saturday)
%wDay of the week (0=Sunday..6=Saturday)
%XYear for the week where Sunday is the first day of the week, numeric, 4 digits; used with %V
%xYear for the week, where Monday is the first day of the week, numeric, 4 digits; used with %v
%YYear, numeric, 4 digits
%yYear, numeric, 2 digits
%%A literal %.
DAY(date)DAY() is a synonym for DAYOFMONTH(). It is available as of MySQL 4.1.1.  
DAYNAME(date) Returns the name of the weekday for date:
    mysql> SELECT DAYNAME('1998-02-05');
            -> 'Thursday'
    
 
DAYOFMONTH(date) Returns the day of the month for date, in the range 1 to 31:
    mysql> SELECT DAYOFMONTH('1998-02-03');
            -> 3
    
 
DAYOFWEEK(date) Returns the weekday index for date (1 = Sunday, 2 = Monday, ... 7 = Saturday). These index values correspond to the ODBC standard.
    mysql> SELECT DAYOFWEEK('1998-02-03');
            -> 3
    
 
DAYOFYEAR(date) Returns the day of the year for date, in the range 1 to 366:
    mysql> SELECT DAYOFYEAR('1998-02-03');
            -> 34
    
 
EXTRACT(type FROM date) The EXTRACT() function uses the same kinds of interval type specifiers as DATE_ADD() or DATE_SUB(), but extracts parts from the date rather than performing date arithmetic.
    mysql> SELECT EXTRACT(YEAR FROM "1999-07-02");
           -> 1999
    mysql> SELECT EXTRACT(YEAR_MONTH FROM "1999-07-02 01:02:03");
           -> 199907
    mysql> SELECT EXTRACT(DAY_MINUTE FROM "1999-07-02 01:02:03");
           -> 20102
    mysql> SELECT EXTRACT(MICROSECOND FROM "2003-01-02 10:30:00.00123");
            -> 123
    
 
FROM_DAYS(N) Given a daynumber N, returns a DATE value:
    mysql> SELECT FROM_DAYS(729669);
            -> '1997-10-07'
    
FROM_DAYS() is not intended for use with values that precede the advent of the Gregorian calendar (1582), because it doesn't take into account the days that were lost when the calendar was changed.
 
FROM_UNIXTIME(unix_timestamp) , FROM_UNIXTIME(unix_timestamp,format) Returns a representation of the unix_timestamp argument as a value in 'YYYY-MM-DD HH:MM:SS' or YYYYMMDDHHMMSS format, depending on whether the function is used in a string or numeric context:
    mysql> SELECT FROM_UNIXTIME(875996580);
            -> '1997-10-04 22:23:00'
    mysql> SELECT FROM_UNIXTIME(875996580) + 0;
            -> 19971004222300
    
If format is given, the result is formatted according to the format string. format may contain the same specifiers as those listed in the entry for the DATE_FORMAT() function:
    mysql> SELECT FROM_UNIXTIME(UNIX_TIMESTAMP(),
        ->                      '%Y %D %M %h:%i:%s %x');
            -> '2003 6th August 06:22:58 2003'
    
 
GET_FORMAT(DATE | TIME | TIMESTAMP, '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. The three possible values for the first argument and the five possible values for the second argument result in 15 possible format strings (for the specifiers used, see the table in the DATE_FORMAT() function description):
Function callResult
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(TIMESTAMP,'USA')'%Y-%m-%d-%H.%i.%s'
GET_FORMAT(TIMESTAMP,'JIS')'%Y-%m-%d %H:%i:%s'
GET_FORMAT(TIMESTAMP,'ISO')'%Y-%m-%d %H:%i:%s'
GET_FORMAT(TIMESTAMP,'EUR')'%Y-%m-%d-%H.%i.%s'
GET_FORMAT(TIMESTAMP,'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'
HOUR(time) Returns the hour for time. The range of the return value will be 0 to 23 for time-of-day values:
    mysql> SELECT HOUR('10:05:03');
            -> 10
    
However, the range of TIME values actually is much larger, so HOUR can return values greater than 23:
    mysql> SELECT HOUR('272:59:59');
            -> 272
    
 
LAST_DAY(date) Takes a date or datetime value and returns the corresponding value for the last day of the month. Returns NULL if the argument is invalid.
    mysql> SELECT LAST_DAY('2003-02-05'), LAST_DAY('2004-02-05');
            -> '2003-02-28', '2004-02-29'
    mysql> SELECT LAST_DAY('2004-01-01 01:01:01');
            -> '2004-01-31'
    mysql> SELECT LAST_DAY('2003-03-32');
            -> NULL
    
LAST_DAY() is available as of MySQL 4.1.1.
 
LOCALTIME , LOCALTIME()LOCALTIME and LOCALTIME() are synonyms for NOW().  
LOCALTIMESTAMP , LOCALTIMESTAMP()LOCALTIMESTAMP and LOCALTIMESTAMP() are synonyms for NOW().  
MAKEDATE(year,dayofyear) Returns a date, given year and day-of-year values. dayofyear must be greater than 0 or the result will NULL.
    mysql> SELECT MAKEDATE(2001,31), MAKEDATE(2001,32);
            -> '2001-01-31', '2001-02-01'
    mysql> SELECT MAKEDATE(2001,365), MAKEDATE(2004,365);
            -> '2001-12-31', '2004-12-30'
    mysql> SELECT MAKEDATE(2001,0);
            -> NULL
    
MAKEDATE() is available as of MySQL 4.1.1.
 
MAKETIME(hour,minute,second) Returns a time value calculated from the hour, minute, and second arguments.
    mysql> SELECT MAKETIME(12,15,30);
            -> '12:15:30'
    
MAKETIME() is available as of MySQL 4.1.1.
 
MICROSECOND(expr) Returns the microseconds from the time or datetime expression expr as a number in the range from 0 to 999999.
    mysql> SELECT MICROSECOND('12:00:00.123456');
            -> 123456
    mysql> SELECT MICROSECOND('1997-12-31 23:59:59.000010');
            -> 10
    
MICROSECOND() is available as of MySQL 4.1.1.
 
MINUTE(time) Returns the minute for time, in the range 0 to 59:
    mysql> SELECT MINUTE('98-02-03 10:05:03');
            -> 5
    
 
MONTH(date) Returns the month for date, in the range 1 to 12:
    mysql> SELECT MONTH('1998-02-03');
            -> 2
    
 
MONTHNAME(date) Returns the name of the month for date:
    mysql> SELECT MONTHNAME('1998-02-05');
            -> 'February'
    
 
NOW() Returns the current date and time as a value in 'YYYY-MM-DD HH:MM:SS' or YYYYMMDDHHMMSS format, depending on whether the function is used in a string or numeric context:
    mysql> SELECT NOW();
            -> '1997-12-15 23:50:26'
    mysql> SELECT NOW() + 0;
            -> 19971215235026
    
 
PERIOD_ADD(P,N) Adds N months to period P (in the format YYMM or YYYYMM). Returns a value in the format YYYYMM. Note that the period argument P is not a date value:
    mysql> SELECT PERIOD_ADD(9801,2);
            -> 199803
    
 
PERIOD_DIFF(P1,P2) Returns the number of months between periods P1 and P2. P1 and P2 should be in the format YYMM or YYYYMM. Note that the period arguments P1 and P2 are not date values:
    mysql> SELECT PERIOD_DIFF(9802,199703);
            -> 11
    
 
QUARTER(date) Returns the quarter of the year for date, in the range 1 to 4:
    mysql> SELECT QUARTER('98-04-01');
            -> 2
    
 
SECOND(time) Returns the second for time, in the range 0 to 59:
    mysql> SELECT SECOND('10:05:03');
            -> 3
    
 
SEC_TO_TIME(seconds) Returns the seconds argument, converted to hours, minutes, and seconds, as a value in 'HH:MM:SS' or HHMMSS format, depending on whether the function is used in a string or numeric context:
    mysql> SELECT SEC_TO_TIME(2378);
            -> '00:39:38'
    mysql> SELECT SEC_TO_TIME(2378) + 0;
            -> 3938
    
 
STR_TO_DATE(str,format) This is the reverse function of the DATE_FORMAT() function. It takes a string str, and a format string format, and returns a DATETIME value. The date, time, or datetime values contained in str should be given in the format indicated by format. For the specifiers that can be used in format, see the table in the DATE_FORMAT() function description. All other characters are just taken verbatim, thus not being interpreted. If str contains an illegal date, time, or datetime value, STR_TO_DATE() returns NULL.
    
    
    
    mysql> SELECT STR_TO_DATE('03.10.2003 09.20', '%d.%m.%Y %H.%i')
            -> 2003-10-03 09:20:00
    mysql> SELECT STR_TO_DATE('10rap', '%crap')
            -> 0000-10-00 00:00:00
    mysql> SELECT STR_TO_DATE('2003-15-10 00:00:00', '%Y-%m-%d %H:%i:%s')
            -> NULL
    
STR_TO_DATE() is available as of MySQL 4.1.1.
 
SUBDATE(date,INTERVAL expr type) , SUBDATE(expr,days) When invoked with the INTERVAL form of the second argument, SUBDATE() is a synonym for DATE_SUB().
    mysql> SELECT DATE_SUB('1998-01-02', INTERVAL 31 DAY);
            -> '1997-12-02'
    mysql> SELECT SUBDATE('1998-01-02', INTERVAL 31 DAY);
            -> '1997-12-02'
    
As of MySQL 4.1.1, the second syntax is allowed, where expr is a date or datetime expression and days is the number of days to be subtracted from expr.
    mysql> SELECT SUBDATE('1998-01-02 12:00:00', 31);
            -> '1997-12-02 12:00:00'
    
 
SUBTIME(expr,expr2)SUBTIME() subtracts expr2 from expr and returns the result. expr is a date or datetime expression, and expr2 is a time expression.
    mysql> SELECT SUBTIME("1997-12-31 23:59:59.999999", "1 1:1:1.000002");
            -> '1997-12-30 22:58:58.999997'
    mysql> SELECT SUBTIME("01:00:00.999999", "02:00:00.999998");
            -> '-00:59:59.999999'
    
SUBTIME() was added in MySQL 4.1.1.
 
SYSDATE()SYSDATE() is a synonym for NOW().  
TIME(expr) Extracts the time part of the time or datetime expression expr.
    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'
    
TIME() is available as of MySQL 4.1.1.
 
TIMEDIFF(expr,expr2)TIMEDIFF() returns the time between the start time expr and the end time expr2. expr and expr2 are time or date-and-time expressions, but both must be of the same type.
    mysql> SELECT TIMEDIFF('2000:01:01 00:00:00', '2000:01:01 00:00:00.000001');
            -> '-00:00:00.000001'
    mysql> SELECT TIMEDIFF('1997-12-31 23:59:59.000001','1997-12-30 01:01:01.000002');
            -> '46:58:57.999999'
    
TIMEDIFF() was added in MySQL 4.1.1.
 
TIMESTAMP(expr) , TIMESTAMP(expr,expr2) With one argument, returns the date or datetime expression expr as a datetime value. With two arguments, adds the time expression expr2 to the date or datetime expression expr and returns a datetime value.
    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'
    
TIMESTAMP() is available as of MySQL 4.1.1.
 
TIMESTAMPADD(interval,int_expr,datetime_expr) Adds the integer expression int_expr to the date or datetime expression datetime_expr. The unit for int_expr is given by the interval argument, which should be one of the following values: FRAC_SECOND, SECOND, MINUTE, HOUR, DAY, WEEK, MONTH, QUARTER, or YEAR. The interval value may be specified using one of keywords as shown, or with a prefix of SQL_TSI_. For example, DAY or SQL_TSI_DAY both are legal.
    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'
    
TIMESTAMPADD() is available as of MySQL 5.0.0.
 
TIMESTAMPDIFF(interval,datetime_expr1,datetime_expr2) Returns the integer difference between the date or datetime expressions datetime_expr1 and datetime_expr2. The unit for the result is given by the interval argument. The legal values for interval are the same as those described in the desription of the TIMESTAMPADD() function.
    mysql> SELECT TIMESTAMPDIFF(MONTH,'2003-02-01','2003-05-01');
            -> 3
    mysql> SELECT TIMESTAMPDIFF(YEAR,'2002-05-01','2001-01-01');
            -> -1
    
TIMESTAMPDIFF() is available as of MySQL 5.0.0.
 
TIME_FORMAT(time,format) This is used like the DATE_FORMAT() function, but the format string may contain only those format specifiers that handle hours, minutes, and seconds. Other specifiers produce a NULL value or 0. If the time value contains an hour part that is greater than 23, the %H and %k hour 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'
    
 
TIME_TO_SEC(time) Returns the time argument, converted to seconds:
    mysql> SELECT TIME_TO_SEC('22:23:00');
            -> 80580
    mysql> SELECT TIME_TO_SEC('00:39:38');
            -> 2378
    
 
TO_DAYS(date) Given a date date, returns a daynumber (the number of days since year 0):
    mysql> SELECT TO_DAYS(950501);
            -> 728779
    mysql> SELECT TO_DAYS('1997-10-07');
            -> 729669
    
TO_DAYS() is not intended for use with values that precede the advent of the Gregorian calendar (1582), because it doesn't take into account the days that were lost when the calendar was changed.
 
UNIX_TIMESTAMP() , UNIX_TIMESTAMP(date) If called with no argument, returns a Unix timestamp (seconds since '1970-01-01 00:00:00' GMT) as an unsigned integer. If UNIX_TIMESTAMP() is called with a date argument, it returns the value of the argument as seconds since '1970-01-01 00:00:00' GMT. date may be a DATE string, a DATETIME string, a TIMESTAMP, or a number in the format YYMMDD or YYYYMMDD in local time:
    mysql> SELECT UNIX_TIMESTAMP();
            -> 882226357
    mysql> SELECT UNIX_TIMESTAMP('1997-10-04 22:23:00');
            -> 875996580
    
When UNIX_TIMESTAMP is used on a TIMESTAMP column, the function returns the internal timestamp value directly, with no implicit ``string-to-Unix-timestamp'' conversion. If you pass an out-of-range date to UNIX_TIMESTAMP() it returns 0, but please note that only basic checking is performed (year 1970-2037, month 01-12, day 01-31). If you want to subtract UNIX_TIMESTAMP() columns, you may want to cast the result to signed integers. See Cast Functions.
 
UTC_DATE , UTC_DATE() Returns the current UTC date as a value in 'YYYY-MM-DD' or YYYYMMDD format, depending on whether the function is used in a string or numeric context:
    mysql> SELECT UTC_DATE(), UTC_DATE() + 0;
            -> '2003-08-14', 20030814
    
UTC_DATE() is available as of MySQL 4.1.1.
 
UTC_TIME , UTC_TIME() Returns the current UTC time as a value in 'HH:MM:SS' or HHMMSS format, depending on whether the function is used in a string or numeric context:
    mysql> SELECT UTC_TIME(), UTC_TIME() + 0;
            -> '18:07:53', 180753
    
UTC_TIME() is available as of MySQL 4.1.1.
 
UTC_TIMESTAMP , UTC_TIMESTAMP() Returns the current UTC date and time as a value in 'YYYY-MM-DD HH:MM:SS' or YYYYMMDDHHMMSS format, depending on whether the function is used in a string or numeric context:
    mysql> SELECT UTC_TIMESTAMP(), UTC_TIMESTAMP() + 0;
            -> '2003-08-14 18:08:04', 20030814180804
    
UTC_TIMESTAMP() is available as of MySQL 4.1.1.
 
WEEK(date [,mode]) The function returns the week number for date. The two-argument form of WEEK() allows you to specify whether the week starts on Sunday or Monday and whether the return value should be in the range 0-53 or 1-52. When mode argument is omitted the value of a default_week_format server variable (or 0 in MySQL 4.0 or earlier) is assumed. See SET OPTION. The following table demonstrates how the mode argument works:
ValueMeaning
0 Week starts on Sunday; return value range is 0 to 53; week 1 is the first week that starts in this year
1 Week starts on Monday; return value range is 0 to 53; week 1 is the first week that has more than 3 days in this year
2 Week starts on Sunday; return value range is 1 to 53; week 1 is the first week that starts in this year
3 Week starts on Monday; return value range is 1 to 53; week 1 is the first week that has more than 3 days in this year
4 Week starts on Sunday; return value range is 0 to 53; week 1 is the first week that has more than 3 days in this year
5 Week starts on Monday; return value range is 0 to 53; week 1 is the first week that starts in this year
6 Week starts on Sunday; return value range is 1 to 53; week 1 is the first week that has more than 3 days in this year
7 Week starts on Monday; return value range is 1 to 53; week 1 is the first week that starts in this year
WEEKDAY(date) Returns the weekday index for date (0 = Monday, 1 = Tuesday, ... 6 = Sunday):
    mysql> SELECT WEEKDAY('1998-02-03 22:23:00');
            -> 1
    mysql> SELECT WEEKDAY('1997-11-05');
            -> 2
    
 
WEEKOFYEAR(date) Returns the calendar week of the date as a number in the range from 1 to 53.
    mysql> SELECT WEEKOFYEAR('1998-02-20');
            -> 8
    
WEEKOFYEAR() is available as of MySQL 4.1.1.
 
YEAR(date) Returns the year for date, in the range 1000 to 9999:
    mysql> SELECT YEAR('98-02-03');
            -> 1998
    
 
YEARWEEK(date) , YEARWEEK(date,start) Returns year and week for a date. The start argument works exactly like the start argument to WEEK(). Note that 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:
    mysql> SELECT YEARWEEK('1987-01-01');
            -> 198653
    
Note that the week number is different from what the WEEK() function would return (0) for optional arguments 0 or 1, as WEEK() then returns the week in the context of the given year.