date_trunc
date_trunc
date_trunc
Description
Syntax
DATETIME DATE_TRUNC(DATETIME datetime, VARCHAR unit)
Truncates datetime in the specified time unit.
datetime is a legal date expression.
unit is the time unit you want to truncate. The optional values are as follows: [second,minute,hour,day,week,month,quarter,year]。
If unit does not meet the above optional values, the result will return NULL.
example
mysql> select date_trunc('2010-12-02 19:28:30', 'second');
+-------------------------------------------------+
| date_trunc('2010-12-02 19:28:30', 'second') |
+-------------------------------------------------+
| 2010-12-02 19:28:30 |
+-------------------------------------------------+
mysql> select date_trunc('2010-12-02 19:28:30', 'minute');
+-------------------------------------------------+
| date_trunc('2010-12-02 19:28:30', 'minute') |
+-------------------------------------------------+
| 2010-12-02 19:28:00 |
+-------------------------------------------------+
mysql> select date_trunc('2010-12-02 19:28:30', 'hour');
+-------------------------------------------------+
| date_trunc('2010-12-02 19:28:30', 'hour') |
+-------------------------------------------------+
| 2010-12-02 19:00:00 |
+-------------------------------------------------+
mysql> select date_trunc('2010-12-02 19:28:30', 'day');
+-------------------------------------------------+
| date_trunc('2010-12-02 19:28:30', 'day') |
+-------------------------------------------------+
| 2010-12-02 00:00:00 |
+-------------------------------------------------+
mysql> select date_trunc('2010-12-02 19:28:30', 'week');
+-------------------------------------------+
| date_trunc('2010-12-02 19:28:30', 'week') |
+-------------------------------------------+
| 2010-11-29 00:00:00 |
+-------------------------------------------+
mysql> select date_trunc('2010-12-02 19:28:30', 'month');
+-------------------------------------------------+
| date_trunc('2010-12-02 19:28:30', 'month') |
+-------------------------------------------------+
| 2010-12-01 00:00:00 |
+-------------------------------------------------+
mysql> select date_trunc('2010-12-02 19:28:30', 'quarter');
+-------------------------------------------------+
| date_trunc('2010-12-02 19:28:30', 'quarter') |
+-------------------------------------------------+
| 2010-10-01 00:00:00 |
+-------------------------------------------------+
mysql> select date_trunc('2010-12-02 19:28:30', 'year');
+-------------------------------------------------+
| date_trunc('2010-12-02 19:28:30', 'year') |
+-------------------------------------------------+
| 2010-01-01 00:00:00 |
+-------------------------------------------------+
keywords
DATE_TRUNC,DATE,DATETIME
