IFNULL

Compares two expressions. Returns <expression1> if it’s non-NULL, otherwise returns <expression2>.

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Syntax

IFNULL(<expression1>, <expression2>)

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Parameters

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Return Types

Same as input type

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Remarks

Use ZEROIFNULL(<expression>) as a synonym shorthand for IFNULL(<expression>, 0). IFNULL(a, b) has the same behaviour as COALESCE(a, b).

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Example

The following truth table demonstrates values that IFNULL returns based on the values of two columns: level and player_id:

SELECT level, player_id, IFNULL(level, player_id), IFNULL(player_id, level)
FROM players;