Extracts the corresponding date part from a date or timestamp.
These functions are alternatives to using the DATE_PART (or EXTRACT) function with the equivalent date part (see Supported date and time parts).
YEAR( <date_or_timestamp_expr> ) YEAROFWEEK( <date_or_timestamp_expr> ) YEAROFWEEKISO( <date_or_timestamp_expr> ) DAY( <date_or_timestamp_expr> ) DAYOFMONTH( <date_or_timestamp_expr> ) DAYOFWEEK( <date_or_timestamp_expr> ) DAYOFWEEKISO( <date_or_timestamp_expr> ) DAYOFYEAR( <date_or_timestamp_expr> ) WEEK( <date_or_timestamp_expr> ) WEEKOFYEAR( <date_or_timestamp_expr> ) WEEKISO( <date_or_timestamp_expr> ) MONTH( <date_or_timestamp_expr> ) QUARTER( <date_or_timestamp_expr> )
Copy
Arguments¶date_or_timestamp_expr
A date or a timestamp, or an expression that can be evaluated to a date or a timestamp.
This function returns a value of type NUMBER.
Usage notes¶Function name
Date part extracted from input date or timestamp
Possible values
YEAR
Year
Any valid year (for example, 2025)
YEAROFWEEK [1]
Year that the extracted week belongs to
Any valid year (for example, 2025)
YEAROFWEEKISO
Year that the extracted week belongs to using ISO semantics
Any valid year (for example, 2025)
DAY , DAYOFMONTH
Day (number) of the month
1 to 31
DAYOFWEEK [1]
Day (number) of the week
0 to 7
DAYOFWEEKISO
Day (number) of the week using ISO semantics
1 to 7
DAYOFYEAR
Day (number) of the year
1 to 366
WEEK , WEEKOFYEAR [1]
Week (number) of the year
1 to 54
WEEKISO
Week (number) of the year using ISO semantics
1 to 53
MONTH
Month (number) of the year
1 to 12
QUARTER
Quarter (number) of the year
1 to 4
[1] Results dictated by the values set for the WEEK_OF_YEAR_POLICY and/or WEEK_START session parameters.
For details about ISO semantics and the parameter, see Calendar weeks and weekdays.
Examples¶The following example demonstrates the use of the functions YEAR, QUARTER, MONTH, DAY, DAYOFWEEK, and DAYOFYEAR:
SELECT '2025-04-11T23:39:20.123-07:00'::TIMESTAMP AS tstamp,
YEAR(tstamp) AS "YEAR",
QUARTER(tstamp) AS "QUARTER OF YEAR",
MONTH(tstamp) AS "MONTH",
DAY(tstamp) AS "DAY",
DAYOFMONTH(tstamp) AS "DAY OF MONTH",
DAYOFYEAR(tstamp) AS "DAY OF YEAR";
Copy
+-------------------------+------+-----------------+-------+-----+--------------+-------------+ | TSTAMP | YEAR | QUARTER OF YEAR | MONTH | DAY | DAY OF MONTH | DAY OF YEAR | |-------------------------+------+-----------------+-------+-----+--------------+-------------| | 2025-04-11 23:39:20.123 | 2025 | 2 | 4 | 11 | 11 | 101 | +-------------------------+------+-----------------+-------+-----+--------------+-------------+
The following example demonstrates the use of the functions WEEK, WEEKISO, WEEKOFYEAR, YEAROFWEEK, and YEAROFWEEKISO. The session parameter WEEK_OF_YEAR_POLICY is set to 1, so that the first week of the year is the week that contains January 1st of that year.
ALTER SESSION SET WEEK_OF_YEAR_POLICY = 1;
Copy
SELECT '2016-01-02T23:39:20.123-07:00'::TIMESTAMP AS tstamp,
WEEK(tstamp) AS "WEEK",
WEEKISO(tstamp) AS "WEEK ISO",
WEEKOFYEAR(tstamp) AS "WEEK OF YEAR",
YEAROFWEEK(tstamp) AS "YEAR OF WEEK",
YEAROFWEEKISO(tstamp) AS "YEAR OF WEEK ISO";
Copy
+-------------------------+------+----------+--------------+--------------+------------------+ | TSTAMP | WEEK | WEEK ISO | WEEK OF YEAR | YEAR OF WEEK | YEAR OF WEEK ISO | |-------------------------+------+----------+--------------+--------------+------------------| | 2016-01-02 23:39:20.123 | 1 | 53 | 1 | 2016 | 2015 | +-------------------------+------+----------+--------------+--------------+------------------+
The following example also demonstrates the use of the functions WEEK, WEEKISO, WEEKOFYEAR, YEAROFWEEK, and YEAROFWEEKISO. The session parameter WEEK_OF_YEAR_POLICY is set to indicate that the first week of the year is the first week of the year that contains at least four days from that year. In this example, the week December 27, 2015 through January 2, 2016 is considered the last week of 2015, not the first week of 2016. Even though the week contains Friday January 1, 2016, less than half of the week is in 2016.
ALTER SESSION SET WEEK_OF_YEAR_POLICY = 0;
Copy
SELECT '2016-01-02T23:39:20.123-07:00'::TIMESTAMP AS tstamp,
WEEK(tstamp) AS "WEEK",
WEEKISO(tstamp) AS "WEEK ISO",
WEEKOFYEAR(tstamp) AS "WEEK OF YEAR",
YEAROFWEEK(tstamp) AS "YEAR OF WEEK",
YEAROFWEEKISO(tstamp) AS "YEAR OF WEEK ISO";
Copy
+-------------------------+------+----------+--------------+--------------+------------------+ | TSTAMP | WEEK | WEEK ISO | WEEK OF YEAR | YEAR OF WEEK | YEAR OF WEEK ISO | |-------------------------+------+----------+--------------+--------------+------------------| | 2016-01-02 23:39:20.123 | 53 | 53 | 53 | 2015 | 2015 | +-------------------------+------+----------+--------------+--------------+------------------+
The following example demonstrates the use of the functions DAYOFWEEK and DAYOFWEEKISO. The session parameter WEEK_START is set to indicate that the week starts on Sunday.
ALTER SESSION SET WEEK_START = 7;
Copy
The timestamp in the following query is for April 5, 2025, which was a Saturday. The DAYOFWEEK function returns 7 for Saturday, because the first day of the week is set to Sunday. The DAYOFWEEKISO function returns 6 because the first day of the week using ISO semantics is Monday. For more information about ISO semantics and the WEEK_START parameter, see Calendar weeks and weekdays.
SELECT '2025-04-05T23:39:20.123-07:00'::TIMESTAMP AS tstamp,
DAYOFWEEK(tstamp) AS "DAY OF WEEK",
DAYOFWEEKISO(tstamp) AS "DAY OF WEEK ISO";
Copy
+-------------------------+-------------+-----------------+ | TSTAMP | DAY OF WEEK | DAY OF WEEK ISO | |-------------------------+-------------+-----------------| | 2025-04-05 23:39:20.123 | 7 | 6 | +-------------------------+-------------+-----------------+
The following example also demonstrates the use of the functions DAYOFWEEK and DAYOFWEEKISO. The session parameter WEEK_START is set to indicate that the week starts on Monday.
ALTER SESSION SET WEEK_START = 1;
Copy
SELECT '2025-04-05T23:39:20.123-07:00'::TIMESTAMP AS tstamp,
DAYOFWEEK(tstamp) AS "DAY OF WEEK",
DAYOFWEEKISO(tstamp) AS "DAY OF WEEK ISO";
Copy
+-------------------------+-------------+-----------------+ | TSTAMP | DAY OF WEEK | DAY OF WEEK ISO | |-------------------------+-------------+-----------------| | 2025-04-05 23:39:20.123 | 6 | 6 | +-------------------------+-------------+-----------------+
For more examples, see Working with date and time values.
For more detailed examples of the week-related functions (DAYOFWEEK, WEEK, WEEKOFYEAR, YEAROFWEEK, and so on), see Calendar weeks and weekdays.
RetroSearch is an open source project built by @garambo | Open a GitHub Issue
Search and Browse the WWW like it's 1997 | Search results from DuckDuckGo
HTML:
3.2
| Encoding:
UTF-8
| Version:
0.7.4