Transaction is rolled back after commit? - sql-server

Question

I'm experiencing some problems that look a LOT like a transaction in a stored procedure has been rolled back, even though I'm fairly certain that it was committed, since the output variable isn't set until after the commit, and the user gets the value of the output variable (I know, because they print it out and I also set up a log table where i input the value of the output variable).
In theory someone COULD manually delete and update the data such that it would look like a rollback, but it is extremely unlikely.
So, I'm hoping someone can spot some kind of structural mistake in my stored procedure. Meet BOB:
CREATE procedure [dbo].[BOB] (#output_id int OUTPUT, #output_msg varchar(255) OUTPUT)
as
BEGIN
SET NOCOUNT ON
DECLARE #id int
DECLARE #record_id int
SET #output_id = 1
-- some preliminary if-statements that doesn't alter any data, but might do a RETURN
SET XACT_ABORT ON
BEGIN TRANSACTION
BEGIN TRY
--insert into table A
SET #id = SCOPE_IDENTITY()
--update table B
DECLARE csr cursor local FOR
SELECT [some stuff] and record_id
FROM temp_table_that_is_not_actually_a_temporary_table
open csr
fetch next from csr into [some variables], #record_id
while ##fetch_status=0
begin
--check type of item + if valid
IF (something)
BEGIN
SET SOME VARIABLE
END
ELSE
BEGIN
ROLLBACK TRANSACTION
SET #output_msg = 'item does not exist'
SET #output_id = 0
RETURN
END
--update table C
--update table D
--insert into table E
--execute some other stored procedure (without transactions)
if (something)
begin
--insert into table F
--update table C again
end
DELETE FROM temp_table_that_is_not_actually_a_temporary_table WHERE record_id=#record_id
fetch next from csr into [some variables], #record_id
end
close csr
deallocate csr
COMMIT TRANSACTION
SET #output_msg = 'ok'
SET #output_id = #id
END TRY
BEGIN CATCH
ROLLBACK TRANSACTION
SET #output_msg = 'transaction failed !'
SET #output_id = 0
INSERT INTO errors (record_time, sp_name, sp_msg, error_msg)
VALUES (getdate(), 'BOB', #output_msg, error_message())
END CATCH
RETURN
END
I know, my user gets an #output_id that is the SCOPE_IDENTITY() and he also gets an #output_msg that says 'ok'. Is there ANY way he can get those outputs without the transaction getting committed?
Thank you.

Answer 1

You know the problem is that transaction dose NOT support rollback on variables because there is no data change inside database. Either commit or rollback of the transactions ONLY make difference on those database objects (tables, temp table, etc.), NOT THE VARIABLES (including table variables).
--EDIT
declare #v1 int = 0, #v2 int = 0, #v3 int = 0
set #v2 = 1
begin tran
set #v1 = 1
commit tran
begin tran
set #v3 = 1
rollback tran
select #v1 as v1, #v2 as v2, #v3 as v3
RESULT is as follows

Answer 2

Personally I never used transactions in stored procedures, especially when they are used simultaniously by many people. I seriously avoid cursors as well.
I think I would go with passing the involved rows of temp_table_that_is_not_actually_a_temporary_table into a real temp table and then go with an if statement for all rows together. That's so simple in tsql:
select (data) into #temp from (normal_table) where (conditions).
What's the point of checking each row, doing the job and then rollback the whole thing if say the last row doesn't meet the condition? Do the check for all of them at once, do the job for all of them at once. That's what sql is all about.