SQL Server Check for IsNull and for Zero

Question

I have the following:

set @SomeVariable = @AnotherVariable/isnull(@VariableEqualToZero,1) - 1

If @VariableEqualToZero is null it substitutes the 1. I need it to substitute 1 if @VariableEqualToZero = 0 as well. How do I do this?

Answer 1

set @SomeVariable = @AnotherVariable / coalesce(case when @VariableEqualToZero = 0 then 1 else @VariableEqualToZero end, 1) - 1

Answer 2

set @SomeVariable = @AnotherVariable /
(case when isnull(@VariableEqualToZero, 0) = 0 then 1 else
@VariableEqualToZero end) - 1

Answer 3

You use CASE

instead of

ISNULL(@VariableEqualToZero,1)

use

CASE WHEN @VariableEqualToZero IS NULL OR @VariableEqualToZero = 0 THEN 1 ELSE @VariableEqualToZero END

COALESCE and ISNULL are essentially just shortcuts for a CASE statement. You can consult the help for the syntax of CASE.