coalesce

Description

Returns the first non-NULL expression among the input parameters. Returns NULL if non-NULL expressions cannot be found.

Syntax

coalesce(expr1,...);

Parameters

expr1: the input expressions, which must evaluate to compatible data types.

Return value

The return value has the same type as expr1.

Examples

mysql> select coalesce(3,NULL,1,1);
+-------------------------+
| coalesce(3, NULL, 1, 1) |
+-------------------------+
|                       3 |
+-------------------------+
1 row in set (0.00 sec)