14.13. Date and Time Functions and Operators

Date and Time Operators

Operator

Example

Result

+

date '2012-08-08' + interval '2' day

2012-08-10

+

time '01:00' + interval '3' hour

04:00:00.000

+

timestamp '2012-08-08 01:00' + interval '29' hour

2012-08-09 06:00:00.000

+

timestamp '2012-10-31 01:00' + interval '1' month

2012-11-30 01:00:00.000

+

interval '2' day + interval '3' hour

2 03:00:00.000

+

interval '3' year + interval '5' month

3-5

-

date '2012-08-08' - interval '2' day

2012-08-06

-

time '01:00' - interval '3' hour

22:00:00.000

-

timestamp '2012-08-08 01:00' - interval '29' hour

2012-08-06 20:00:00.000

-

timestamp '2012-10-31 01:00' - interval '1' month

2012-09-30 01:00:00.000

-

interval '2' day - interval '3' hour

1 21:00:00.000

-

interval '3' year - interval '5' month

2-7

Time Zone Conversion

The AT TIME ZONE operator sets the time zone of a timestamp:

SELECT timestamp '2012-10-31 01:00 UTC';
2012-10-31 01:00:00.000 UTC

SELECT timestamp '2012-10-31 01:00 UTC' AT TIME ZONE 'America/Los_Angeles';
2012-10-30 18:00:00.000 America/Los_Angeles

Date and Time Functions

current_date -> date

Returns the current date as of the start of the query.

current_time -> time with time zone

Returns the current time as of the start of the query.

current_timestamp -> timestamp with time zone

Returns the current timestamp as of the start of the query.

current_timezone() → varchar

Returns the current time zone in the format defined by IANA (e.g., America/Los_Angeles) or as fixed offset from UTC (e.g., +08:35)

date(x) → date

This is an alias for CAST(x AS date).

from_iso8601_timestamp(string) → timestamp with time zone

Parses the ISO 8601 formatted string into a timestamp with time zone.

from_iso8601_date(string) → date

Parses the ISO 8601 formatted string into a date.

from_unixtime(unixtime) → timestamp

Returns the UNIX timestamp unixtime as a timestamp. unixtime is the number of seconds since 1970-01-01 00:00:00.

from_unixtime(unixtime, string) → timestamp with time zone

Returns the UNIX timestamp unixtime as a timestamp with time zone using string for the time zone. unixtime is the number of seconds since 1970-01-01 00:00:00.

from_unixtime(unixtime, hours, minutes) → timestamp with time zone

Returns the UNIX timestamp unixtime as a timestamp with time zone using hours and minutes for the time zone offset. unixtime is the number of seconds since 1970-01-01 00:00:00.

localtime -> time

Returns the current time as of the start of the query.

localtimestamp -> timestamp

Returns the current timestamp as of the start of the query.

now() → timestamp with time zone

This is an alias for current_timestamp.

to_iso8601(x) → varchar

Formats x as an ISO 8601 string. x can be date, timestamp, or timestamp with time zone.

to_milliseconds(interval) → bigint

Returns the day-to-second interval as milliseconds.

to_unixtime(timestamp) → double

Returns timestamp as a UNIX timestamp.

Note

The following SQL-standard functions do not use parenthesis:

  • current_date

  • current_time

  • current_timestamp

  • localtime

  • localtimestamp

Truncation Function

The date_trunc function supports the following units:

Unit

Example Truncated Value

second

2001-08-22 03:04:05.000

minute

2001-08-22 03:04:00.000

hour

2001-08-22 03:00:00.000

day

2001-08-22 00:00:00.000

week

2001-08-20 00:00:00.000

month

2001-08-01 00:00:00.000

quarter

2001-07-01 00:00:00.000

year

2001-01-01 00:00:00.000

The above examples use the timestamp 2001-08-22 03:04:05.321 as the input.

date_trunc(unit, x) → [same as input]

Returns x truncated to unit.

Interval Functions

The functions in this section support the following interval units:

Unit

Description

millisecond

Milliseconds

second

Seconds

minute

Minutes

hour

Hours

day

Days

week

Weeks

month

Months

quarter

Quarters of a year

year

Years

date_add(unit, value, timestamp) → [same as input]

Adds an interval value of type unit to timestamp. Subtraction can be performed by using a negative value.

date_diff(unit, timestamp1, timestamp2) → bigint

Returns timestamp2 - timestamp1 expressed in terms of unit.

Duration Function

The parse_duration function supports the following units:

Unit

Description

ns

Nanoseconds

us

Microseconds

ms

Milliseconds

s

Seconds

m

Minutes

h

Hours

d

Days

parse_duration(string) → interval

Parses string of format value unit into an interval, where value is fractional number of unit values:

SELECT parse_duration('42.8ms'); -- 0 00:00:00.043
SELECT parse_duration('3.81 d'); -- 3 19:26:24.000
SELECT parse_duration('5m');     -- 0 00:05:00.000

MySQL Date Functions

The functions in this section use a format string that is compatible with the MySQL date_parse and str_to_date functions. The following table, based on the MySQL manual, describes the format specifiers:

Specifier

Description

%a

Abbreviated weekday name (Sun .. Sat)

%b

Abbreviated month name (Jan .. Dec)

%c

Month, numeric (1 .. 12) 4

%D

Day of the month with English suffix (0th, 1st, 2nd, 3rd, …)

%d

Day of the month, numeric (01 .. 31) 4

%e

Day of the month, numeric (1 .. 31) 4

%f

Fraction of second (6 digits for printing: 000000 .. 999000; 1 - 9 digits for parsing: 0 .. 999999999) 1

%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 (01 .. 12) 4

%p

AM or PM

%r

Time, 12-hour (hh:mm:ss followed by AM or 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

%u

Week (00 .. 53), where Monday is the first day of the week

%V

Week (01 .. 53), where Sunday is the first day of the week; used with %X

%v

Week (01 .. 53), where Monday is the first day of the week; used with %x

%W

Weekday name (Sunday .. Saturday)

%w

Day of the week (0 .. 6), where Sunday is the first day of the week 3

%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) 2

%%

A literal % character

%x

x, for any x not listed above

1

Timestamp is truncated to milliseconds.

2

When parsing, two-digit year format assumes range 1970 .. 2069, so “70” will result in year 1970 but “69” will produce 2069.

3

This specifier is not supported yet. Consider using day_of_week() (it uses 1-7 instead of 0-6).

4(1,2,3,4)

This specifier does not support 0 as a month or day.

Warning

The following specifiers are not currently supported: %D %U %u %V %w %X

date_format(timestamp, format) → varchar

Formats timestamp as a string using format.

date_parse(string, format) → timestamp

Parses string into a timestamp using format.

Java Date Functions

The functions in this section use a format string that is compatible with JodaTime’s DateTimeFormat pattern format.

format_datetime(timestamp, format) → varchar

Formats timestamp as a string using format.

parse_datetime(string, format) → timestamp with time zone

Parses string into a timestamp with time zone using format.

Extraction Function

The extract function supports the following fields:

Field

Description

YEAR

year()

QUARTER

quarter()

MONTH

month()

WEEK

week()

DAY

day()

DAY_OF_MONTH

day()

DAY_OF_WEEK

day_of_week()

DOW

day_of_week()

DAY_OF_YEAR

day_of_year()

DOY

day_of_year()

YEAR_OF_WEEK

year_of_week()

YOW

year_of_week()

HOUR

hour()

MINUTE

minute()

SECOND

second()

TIMEZONE_HOUR

timezone_hour()

TIMEZONE_MINUTE

timezone_minute()

The types supported by the extract function vary depending on the field to be extracted. Most fields support all date and time types.

extract(field FROM x) → bigint

Returns field from x.

Note

This SQL-standard function uses special syntax for specifying the arguments.

Convenience Extraction Functions

day(x) → bigint

Returns the day of the month from x.

day_of_month(x) → bigint

This is an alias for day().

day_of_week(x) → bigint

Returns the ISO day of the week from x. The value ranges from 1 (Monday) to 7 (Sunday).

day_of_year(x) → bigint

Returns the day of the year from x. The value ranges from 1 to 366.

dow(x) → bigint

This is an alias for day_of_week().

doy(x) → bigint

This is an alias for day_of_year().

hour(x) → bigint

Returns the hour of the day from x. The value ranges from 0 to 23.

millisecond(x) → bigint

Returns the millisecond of the second from x.

minute(x) → bigint

Returns the minute of the hour from x.

month(x) → bigint

Returns the month of the year from x.

quarter(x) → bigint

Returns the quarter of the year from x. The value ranges from 1 to 4.

second(x) → bigint

Returns the second of the minute from x.

timezone_hour(timestamp) → bigint

Returns the hour of the time zone offset from timestamp.

timezone_minute(timestamp) → bigint

Returns the minute of the time zone offset from timestamp.

week(x) → bigint

Returns the ISO week of the year from x. The value ranges from 1 to 53.

week_of_year(x) → bigint

This is an alias for week().

year(x) → bigint

Returns the year from x.

year_of_week(x) → bigint

Returns the year of the ISO week from x.

yow(x) → bigint

This is an alias for year_of_week().