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Test whether an expression is NULL:
SELECT ISNULL(NULL);The ISNULL() function returns 1 or 0 depending on whether an expression is NULL. If expression is NULL, this function returns 1. Otherwise, it returns 0.
expression )
Required. The value to test
From MySQL 4.0
Test whether an expression is NULL:
SELECT ISNULL("");Test whether an expression is NULL:
SELECT ISNULL(350);Test whether an expression is NULL:
SELECT ISNULL("Hello world!");❮ MySQL Functions