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SQL Server function: isNull

isNull(expr, val-if-expr-is-null)

isNull evaluates to the the value of expr except if this value is null. In this case, the function evaluates to the value of val-if-expr-is-null.

See also

Oracle's equivalent of isNull is nvl (I am not sure if isNull also evaluates its expressions lazily, however).

The SQL Server function isNull behaves differently from VBA's/Access's isNull function.

T-SQL functions

Oracle's equivalent for isNull is roughly nvl.