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. The supported data types are BOOLEAN, TINYINT, SMALLINT, INT, BIGINT, LARGEINT, FLOAT, DOUBLE, DATETIME, DATE, DECIMALV2, DECIMAL32, DECIMAL64, DECIMAL128, VARCHAR, BITMAP, PERCENTILE, HLL, and TIME.

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)