COALESCE¶

The COALESCE function returns the first non-NULL value from the list of expressions.

Syntax¶

COALESCE(expr1, expr2, ...)

Parameters¶

• expr1, expr2, ... – Expressions evaluated in order. At least one expression must be provided.

Examples¶

CREATE TABLE example (a INT NULL, b INT NULL);
INSERT INTO example VALUES (NULL, 2), (3, NULL), (NULL, NULL);

SELECT COALESCE(a, b, 0) AS result FROM example;

This returns 2, 3 and 0 for the three rows.

Notes¶

If all arguments are NULL, the result is NULL.