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COALESCE

Checks from left to right whether NULL arguments were passed and returns the first non-NULL argument.

Syntax​

COALESCE(x,...)

Arguments​

ArgumentsDescription
xThe original value.

Return Type​

Returns the first non-NULL argument, returns NULL if all arguments are NULL.

Examples​

SELECT COALESCE(NULL, 1, 2);

+----------------------+
| COALESCE(NULL, 1, 2) |
+----------------------+
|                    1 |
+----------------------+