Question

How do I alter the following procedure in such a way that if insert statement is not successfully executed because of PrimaryKey or something the Delete Statement must also not be executed and further more it should generate an error message that I would Write myself.

CREATE PROCEDURE [dbo].[ReAdmissionInsert]
@GRNo varchar(4),
@ClassId numeric(2),
@FacultyId numeric(1),
@Section varchar(1),
@SessionId numeric(1)
AS
begin
insert into ReAdmissionDtl(GRNo,ClassId,FacultyId,Section,SessionId) values(@GRNo,@ClassId,@FacultyId,@Section,@SessionId)
delete from Discharge where GRNo = @GRNo
end

Answer 1

Use a transaction and a try catch block. Raise your error in the catch block, like so:

CREATE PROCEDURE [dbo].[ReAdmissionInsert]
@GRNo varchar(4),
@ClassId numeric(2),
@FacultyId numeric(1),
@Section varchar(1),
@SessionId numeric(1)
AS
begin
Begin transaction
Begin try
    insert into ReAdmissionDtl(GRNo,ClassId,FacultyId,Section,SessionId)
       values(@GRNo,@ClassId,@FacultyId,@Section,@SessionId)
    delete from Discharge where GRNo = @GRNo
    Commit transaction
End try
Begin catch
    Rollback
    Raiserror(999999,'my message',16,1)
End catch
end