ISNULL
Use ISNULL to specify a substitute value if the first expression is null.
If the expression_value is not null, it is returned. If it is null, the substitute value is returned.
Syntax
ISNULL(expression, substitute_value)Use ISNULL to specify a substitute value if the first expression is null.
If the expression_value is not null, it is returned. If it is null, the substitute value is returned.
ISNULL(expression, substitute_value)