IN Clause with WHERE clause not getting proper results in SQL Server

Question

 SELECT Col1, Col2, Col3, Col4
   FROM Table1 
  WHERE User1 = @Owner
    AND group1 = @Group
    AND date1 BETWEEN @startDate AND @endDate
    AND Mail LIKE @email
    AND def IN (CASE @InvoiceMethod //Problem is Here 
                  WHEN ''
                    THEN def
                  ELSE (@InvoiceMethod)
               END)

A piece of code from the stored procedure. If am executing this, it's not returning any rows, even though it has some to return. Problem is with the IN clause, if I didn't pass anything to IN clause i.e @InvoiceMethod is null, then I'm getting rows.

If I pass anything to @InvoiceMethod, I'm not getting any rows.

The value in @InvoiceMethod is = 'A','B'

I tried many combinations like 'A','B' or "A","B" without any results.

How to pass values to IN clause please? In which format?

Please help me out of this.

Modified the stored procedure to the following,

Declare @tmpt table (value nvarchar(5) not null)
      SET @InvoiceCount=(select COUNT(*) from dbo.fnSplit(@InvoiceMethod, ','))
    SET @tempVar=1;
    WHILE @tempVar<=(@InvoiceCount)
          BEGIN
        INSERT INTO @tmpt (value) 
        VALUES (@InvoiceMethod);//Here i need to insert array of values to temp   table.like invoicemethod[0],invoicemethod[1]&invoicemethod[2] depends on @InvoiceCount

        SET @tempVar=@tempVar+1;
      END
--DECLARE @tmpt TABLE (value NVARCHAR(5) NOT NULL)
--INSERT INTO @tmpt (value) VALUES (@InvoiceMethod);

 SELECT Col1,Col2,Col3,Col4
   FROM Table1 
  WHERE User1 = @Owner
    AND group1 = @Group
    AND date1 between @startDate AND @endDate
    AND Mail LIKE @email
    AND def IN (SELECT value FROM @tmpt)

But not getting the results as expected :(

Answer 1

Used Splitfunctions to resolve the issue,Modified SQL Query

SELECT Col1, Col2, Col3, Col4
 FROM Table1 
  WHERE User1 = @Owner
AND group1 = @Group
AND date1 BETWEEN @startDate AND @endDate
AND Mail LIKE @email
AND def IN (SELECT * FROM sptFunction(@InvoiceMethod,',')) //Problem is Here (Solved by using split functions)

Answer 2

IMO this isn't a good way to approach this problem, by passing a list of filter values for a column in a comma separated string, as this is almost encouraging a Dynamic Sql approach to the problem (i.e. where you EXEC a built Sql string which pastes in the @InvoiceMethod as a string).

Instead, Sql 2008 has Table Valued Parameters, (and prior to this, you could use Xml), which allows you to pass structured data into a procedure in a table format.

You then just need to join to this table parameter to effect the 1..N valued IN () filtering.

CREATE TYPE ttInvoiceMethods AS TABLE
(
  Method VARCHAR(20)
);
GO

CREATE PROCEDURE dbo.SomeProc 
(
   @InvoiceMethod ttInvoiceMethods READONLY, -- ... Other Params here
)
AS
begin

   SELECT Col1, Col2, ...
   FROM Table1
        INNER JOIN @InvoiceMethod
           ON Table1.def = @InvoiceMethod.Method -- Join here
   WHERE User1 = @Owner
        ... Other Filters here

END

Have a look here for a similar solution with a fiddle.

Edit

The optional parameter (@InvoiceMethod = '') can be handled by changing the JOIN to the TVP with a subquery:

   WHERE
     --  ... Other filters
     AND (Table1.def IN (SELECT Method FROM @InvoiceMethod))
        OR @InvoiceMethod IS NULL)

To Initialize a TVP to NULL, just don't bind to it in C# at all.

Answer 3

I think a variable represetning multiple values with comma is not allowed in the in clause. You should either use string fiunctions (split and join) or go with the temp table solution. I prefer the second.

Use a temporary table to store your values and then pass it to your in statement

DECLARE @tmpt TABLE (value NVARCHAR(5) NOT NULL)

INSERT INTO @tmpt .........
...
...

 SELECT Col1,Col2,Col3,Col4
   FROM Table1 
  WHERE User1 = @Owner
    AND group1 = @Group
    AND date1 BETWEEN @startDate AND @endDate
    AND Mail LIKE @email
    AND def IN (SELECT value FROM @tmpt)