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The EXTRACT function retrieves subfields such as day or hour from date/time values. The source value has to be a value expression of type *timestamp*, *time*, *date*, or *interval*.

*Field* is an identifier or string that identifies the field to extract from the source value. The extract function returns values of type *double precision*.

**Examples:**

The following field names are available:

**day** ::

SELECT EXTRACT(DAY FROM TIMESTAMP '2001-02-16 20:38:40');

Day of the month.

*Result: 16*

**decade** ::

SELECT EXTRACT(DECADE FROM TIMESTAMP '2001-02-16 20:38:40');

The year, divided by 10.

*Result: 200*

**dow** ::

SELECT EXTRACT(DOW FROM TIMESTAMP '2001-02-16 20:38:40');

The day of the week (Sunday is 0, Saturday is 6)

*Result: 5*

**doy** ::

SELECT EXTRACT(DOY FROM TIMESTAMP '2001-02-16 20:38:40');

The day of the year (1 - 365/366)

*Result: 47*

**hour** ::

SELECT EXTRACT(HOUR FROM TIMESTAMP '2001-02-16 20:38:40');

The hour field (0 - 23)

*Result: 20*

**microseconds** ::

SELECT EXTRACT(MICROSECONDS FROM TIME '17:12:28.5');

The seconds field, including fractional parts, multiplied by 1 000 000; note that this includes full seconds

*Result: 28500000*

**minute** ::

SELECT EXTRACT(MINUTE FROM TIMESTAMP '2001-02-16 20:38:40');

The minutes field (0 - 59)

*Result: 38*

**month**

For timestamp values, the number of the month within the year (1 - 12).

For interval values, the number of months (0 - 11). ::

SELECT EXTRACT(MONTH FROM TIMESTAMP '2010-12-29 08:45:27');

*Result: 12* ::

SELECT EXTRACT(MONTH FROM INTERVAL '3 years 4 months');

*Result: 4* ::

SELECT EXTRACT(MONTH FROM INTERVAL '3 years 13 months');

*Result: 1*

**quarter** ::

SELECT EXTRACT(QUARTER FROM TIMESTAMP '2010-12-29 08:45:27');

The quarter of the year (1 - 4) containing the date.

*Result: 4*

**second** ::

SELECT EXTRACT(SECOND FROM TIMESTAMP '2010-12-29 08:45:27');

100

101

The seconds field, including fractional parts (0 - 59)

102

103

*Result: 27* ::

104

105

SELECT EXTRACT(SECOND FROM TIME '08:15:22.5');

106

107

*Result: 22.5*

108

109

**timezone**

110

111

The time zone offset from UTC, measured in seconds.

112

113

**week**

114

115

Returns the week number that a day is in. Weeks are numbered according to ISO 8601:1988.

116

117

ISO 8601:1988 means that if the week containing January 1 has four or more days in the new year, then it is week 1; otherwise it is the last week of the previous year, and the next week is week 1. The ISO-8601 week starts on Monday.

118

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It's possible for early January dates to be part of the 52nd or 53rd week of the previous year. For example, 2011-01-01 was part of the 52nd week of year 2010. ::

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121

SELECT EXTRACT(WEEK FROM TIMESTAMP '2010-01-25 12:44:06');

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123

*Result: 4*

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**year** ::

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SELECT EXTRACT(YEAR FROM TIMESTAMP '2009-02-16 20:38:40');

128

129

*Result: 2009*

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The valid field names for date_part are the same as for extract. ::

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SELECT date_part('day', TIMESTAMP '2010-07-16 10:12:05');

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135

*Result: 16* ::

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SELECT date_part('hour', INTERVAL '5 hours 12 minutes');

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139

*Result: 4*

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