Dynamic SQL using Sp_executesql

Question

I have a stored procedure which I have to rewrite using sp_executesql . I want to use sp_executesql instead of exec because of performance issue on my SQL Server instance.

Here is my code:

ALTER PROCEDURE [dbo].[sp_TestSp1] 
      @Type1 VARCHAR(256)
AS
BEGIN
    SET NOCOUNT ON;

    DECLARE @sqlCommand varchar(2000) = ''
    DECLARE @columnList varchar(1000) = ''
    DECLARE @dynamicSql varchar(1000) = ''

    IF  (@Type1 IS NOT NULL )
    BEGIN
    SET @dynamicSql = @dynamicSql + 'AND tbl1.DTypeID IN ( '+ @Type1+ ' )' 
    END     

SET @columnList = 'SELECT DISTINCT tbl2.ID, Name AS PName '
SET @sqlCommand =  @columnList 
                    + ' FROM tbl1 '
                    + ' INNER JOIN tbl3 ON tbl1.NID= tbl3.NID '
                    + ' INNER JOIN tbl4 ON tbl3.DID = tbl4.DID '
                    + ' WHERE TT=1 AND IsActive=1 AND tbl1.DTypeID IN (1,3,5)' 
                    + @dynamicSql
EXEC (@sqlCommand)

Answer 1

Replace your EXEC (@sqlCommand) statement with the following.

EXECUTE sp_executesql @sqlCommand

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