Question

I need some help with this procedure:

What its supposed to do is try to insert a new user if there is no other with same NAME.

If there is a already an user, it should rollback else commit. But it doesn’t work, it commits anyway.

Any suggestions?

SET ANSI_NULLS ON
SET QUOTED_IDENTIFIER ON
GO

ALTER procedure [dbo].[SP_USUARIOS_INSERT]
@usu_ds varchar(50),
@usu_dt_create datetime,
@usu_dt_lst_log datetime,
@usu_ds_senha varchar(255),
@usu_ds_email varchar(100)
as
begin
declare @varCheckUser varchar(100) = null;
set @varCheckUser = (select COUNT(usu.usu_Ds) from Usuarios usu where usu.usu_ds = @usu_ds);
begin transaction
insert into Usuarios(usu_ds,usu_dt_create,usu_dt_lst_log,usu_ds_senha,usu_ds_email) values(@usu_ds,@usu_dt_create,@usu_dt_lst_log,@usu_ds_senha,@usu_ds_email)
if (@varCheckUser <> null)
begin
 RAISERROR('User already exists',16,1)
 rollback transaction
 return
end
else
begin
commit transaction
end
end

Answer 1

I don’t think that @varCheckUser will ever be NULL, if there is no row it will be 0

set @varCheckUser = (select COUNT(usu.usu_Ds) 
from Usuarios usu where usu.usu_ds = @usu_ds);

this will make it 0

also you check like this for NULL

if (@varCheckUser IS NOT null)

why don’t you do something like this

IF  EXISTS (select 1 
               from Usuarios usu 
                where usu.usu_ds = @usu_ds)
SET @varCheckUser =1

then check that it is not 1

why do you need the tran? Just do something like this

IF  EXISTS (select 1 
                   from Usuarios usu 
                    where usu.usu_ds = @usu_ds)
BEGIN
RAISERROR('User already exists',16,1)
RETURN
END
ELSE
BEGIN
insert into Usuarios(usu_ds,usu_dt_create,usu_dt_lst_log,usu_ds_senha,usu_ds_email)
values(@usu_ds,@usu_dt_create,@usu_dt_lst_log,@usu_ds_senha,@usu_ds_email)

END

Probably a good idea to make usu_ds a primary key or add a unique constraint, that way nobody can update their user name to something that exists and nobody can by mistake use SSMS and change a user name to something that is already in the table