How do check if a parameter is empty or null in Sql Server stored procedure in IF statement?

Question

I read this: How do I check if a Sql server string is null or empty but it not helped me in this situation.

The piece of code from my stored procedure:

I         


        

Answer 1

that is the right behavior.

if you set @item1 to a value the below expression will be true

IF (@item1 IS NOT NULL) OR (LEN(@item1) > 0)

Anyway in SQL Server there is not a such function but you can create your own:

CREATE FUNCTION dbo.IsNullOrEmpty(@x varchar(max)) returns bit as
BEGIN
IF @SomeVarcharParm IS NOT NULL AND LEN(@SomeVarcharParm) > 0
    RETURN 0
ELSE
    RETURN 1
END

Answer 2

To check if variable is null or empty use this:

IF LEN(ISNULL(@var, '')) = 0
    -- Is empty or NULL
ELSE
    -- Is not empty and is not NULL

Answer 3

Of course that works; when @item1 = N'', it IS NOT NULL.

You can define @item1 as NULL by default at the top of your stored procedure, and then not pass in a parameter.