datediff

Description

Syntax

DATETIME DATEDIFF (DATETIME expr1,DATETIME expr2)

Expr1 - expr2 is calculated and the result is accurate to the sky.

Expr1 and expr2 parameters are valid date or date/time expressions.

Note: Only the date part of the value participates in the calculation.

example

mysql> select datediff(CAST('2007-12-31 23:59:59' AS DATETIME), CAST('2007-12-30' AS DATETIME));
+-----------------------------------------------------------------------------------+
| datediff(CAST('2007-12-31 23:59:59' AS DATETIME), CAST('2007-12-30' AS DATETIME)) |
+-----------------------------------------------------------------------------------+
|                                                                                 1 |
+-----------------------------------------------------------------------------------+
mysql> select datediff(CAST('2010-11-30 23:59:59' AS DATETIME), CAST('2010-12-31' AS DATETIME));
+-----------------------------------------------------------------------------------+
| datediff(CAST('2010-11-30 23:59:59' AS DATETIME), CAST('2010-12-31' AS DATETIME)) |
+-----------------------------------------------------------------------------------+
|                                                                               -31 |
+-----------------------------------------------------------------------------------+

keyword

DATEDIFF