Question

I need to insert the selected data from tblA to tblB only if data selected does not exist in tblB. I created a button that will execute this stored procedure.
I cannot figure out what I am doing wrong in my stored procedure, it is not inserting/showing non existing data into tblB.

I am using SQL Server 2008 and ASP.NET.

CREATE PROCEDURE [dbo].[ADDATA]
@EmpFrom varchar(7) 
,@EmpTo varchar(7)   
AS
SET NOCOUNT ON;
DECLARE @affectedRows int
SET @affectedRows = 0;
BEGIN 
    IF NOT EXISTS (SELECT 1 FROM [dbo].[tblA] WHERE @EmpFrom = @EmpTo) 
    SET @affectedRows = @affectedRows + @@ROWCOUNT

BEGIN
INSERT INTO tblB
(EmpNum --- PK
 ,Last_First
 ,Title
 ,NTUserName)
select
@EmpTo
,a.emp_name_lfn
,a.job_title
,a.[user_id]
FROM tblA 
    END
END

Answer 1

Try it this way

CREATE PROCEDURE [dbo].[ADDATA]
@EmpTo varchar(7)   
AS
SET NOCOUNT ON;
DECLARE @affectedRows int
SET @affectedRows = 0;
  BEGIN     
    IF NOT EXISTS (SELECT * FROM [dbo].[tblB] WHERE EmpNum = @EmpTo)
      BEGIN
        INSERT INTO tblB(EmpNum, Last_First, Title, NTUserName)
        SELECT @EmpTo, emp_name_lfn, job_title, [user_id]
        FROM tblA
        WHERE [Whatever_The_EmpNum_Field_Is_Named_In_tblA] = @EmpTo
        SET @affectedRows = @affectedRows + @@ROWCOUNT
      END
  END

Hope this helps,
~ck