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:

IF (@item1 IS NOT NULL) OR (LEN(@item1) > 0)         SELECT @sql = 'SELECT * FROM TEST1'     ELSE         SELECT @sql = 'SELECT * FROM TEST2'  PRINT @sql; 

@item1 is NVARCHAR(1000) type.

When execute this stored procedure, I provided the value for item1

EXEC    [dbo].[my_proc]         @item1 = N'' 

it shows

SELECT * FROM TEST1 // it is correct if @item1 = N'some'

instead of

SELECT * FROM TEST2

It is somewhere a function in sql to verify if a string is null or empty OR I made somewhere a mistake ?

Like in C# -> string.IsNullOrEmpty(myValue)

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