Multiple Roll back for single Transcation - sql-server

I have to update multiple number of rows in table.
My requirement is, If for any reason , the update result returns 0, then the entire transaction should be rolled back.
At the same time if there is any exception occurred, then also the complete transaction must be rolled back.
In short I need to roll back the entire update transaction either if update statement returns 0 or if any exception has been occurred while updating the table.
This is the code I used.
CREATE TYPE [DBO].[EMPLOYEETYPETABLETYPE] AS TABLE
( EmployeeStatusKey INT, EmployeeStatusName VARCHAR(50) )
CREATE PROCEDURE [dbo].[usp_UpdateEmployeeStatusType]
#EmploymentStatusDetails [DBO].[EMPLOYEETYPETABLETYPE] READONLY
AS
BEGIN
SET NOCOUNT ON;
DECLARE #TransactionName varchar(20) = 'UpdateEmployeeStatus';
DECLARE #rowcount1 INT
BEGIN
BEGIN TRY
BEGIN TRANSACTION #TransactionName
UPDATE ES1
SET
ES1.EmployeeStatusName=ES2.EmployeeStatusName
FROM
[dbo].[EmployeeStatusTypes] ES1
INNER JOIN
#EmploymentStatusDetails ES2
ON
ES1.EmployeeStatusKey= ES2.EmployeeStatusKey
SET
#ROWCOUNT1=##ROWCOUNT
IF #rowcount1 =0
GOTO PROBLEM
PROBLEM:
ROLLBACK TRAN #TransactionName
COMMIT
END TRY
BEGIN CATCH
SET #ROWCOUNT1=0
ROLLBACK TRAN #TransactionName
END CATCH
IF #rowcount1 =0
SELECT -178,#rowcount1;
ELSE
SELECT 178,#rowcount1;
END
END
I am passing a datatable to the stored procedure from the C# code.
When I execute the Sp, No error is thrown But When I call it from the C# code I am getting the Exception
Exception: The ROLLBACK TRANSACTION request has no corresponding BEGIN TRANSACTION.
Please help and Thanks in advance....

Remove that awful GOTO
IF #rowcount1 =0
ROLLBACK TRAN #TransactionName
ELSE
COMMIT TRAN #TransactionName
And review TRY-CATCH documentation. You have to check whether there is any transaction to commit or rollback by checking XACT_STATE() value.

I tested your script with simplified one:
BEGIN TRY
print 'A:' + cast(##trancount as varchar)
BEGIN TRANSACTION tranName
print 'B:' + cast(##trancount as varchar)
GOTO PROBLEM -- you can comment this to simulate there is no error
PROBLEM:
begin
ROLLBACK TRAN tranName
print 'there is a problem'
end
print 'C:' + cast(##trancount as varchar)
COMMIT
END TRY
BEGIN CATCH
print 'D:' + cast(##trancount as varchar)
ROLLBACK TRAN tranName
END CATCH
when there is a problem, output is like
A:0
B:1
there is a problem
C:0
D:0
Msg 3903, Level 16, State 1, Line 18
The ROLLBACK TRANSACTION request has no corresponding BEGIN TRANSACTION.
if I comment the GOTO PROBLEM so there is not a problem, output is like this:
A:0
B:1
there is a problem
C:0
D:0
Msg 3903, Level 16, State 1, Line 18
The ROLLBACK TRANSACTION request has no corresponding BEGIN TRANSACTION.
you see that the section under GOTO, still is executing.
finally, the COMMIT still happens where there is not transaction available, so COMMIT throws and error. This means your script throws an exception.
If you get rid of the GOTO, you'll be good. using GOTO is a bad practice anyway.

Related

Insert in catch block causes error: The current transaction cannot be committed and cannot support operations that write to the log file

I have two procedures, one outer procedure and one inner procedure, where I would like to understand the behaviour of the error handling. The inner procedure provokes an error and is trying to insert something in the catch block into a table. After that the error is raised, passed to the outer procedure and then should roll back the transaction.
I'm trying to understand why my code is throwing the error message:
Msg 50000, Level 11, State 1, Procedure dbo.OuterProcedure, Line 21 [Batch Start Line 9]
The current transaction cannot be committed and cannot support operations that write to the log file. Roll back the transaction.
I would expect the following message:
Msg 50000, Level 11, State 1, Procedure dbo.OuterProcedure, Line 21 [Batch Start Line 9]
Error converting data type varchar to numeric.
I know that the issue comes from the catch block in the inner procedure and it happens because I'm trying to insert something into my log table before raising the error. When I switch those statements or delete the insert, I get the actual error message. I also know that it is not smart to do the logging in the inner procedure and inside a transaction that is rolled back anyways.
I would like to understand what is making this transaction a "doomed" transaction even though the XACT_ABORT is set to off.
Full code:
My main procedure:
CREATE PROCEDURE [dbo].[OuterProcedure]
AS
BEGIN
SET XACT_ABORT OFF;
BEGIN TRY
BEGIN TRANSACTION ;
-- do other stuff
EXEC [dbo].[innerprocedure];
-- do other stuff
COMMIT TRANSACTION ;
END TRY
BEGIN CATCH
ROLLBACK TRANSACTION;
DECLARE #ErrText NVARCHAR(2000);
SET #ErrText = ISNULL(ERROR_MESSAGE(), 'nothing')
RAISERROR(#ErrText, 11, 1) WITH NOWAIT
END CATCH;
END;
My inner procedure:
CREATE PROCEDURE [dbo].[InnerProcedure]
AS
BEGIN
SET XACT_ABORT OFF;
SET NOCOUNT ON;
BEGIN TRY
-- do other stuff
-- provoke error
SELECT
CASE
WHEN 1 = 0
THEN 0.0
ELSE ''
END;
-- do other stuff
END TRY
BEGIN CATCH
DECLARE #ErrText NVARCHAR(2000);
SELECT
#ErrText = ISNULL(ERROR_MESSAGE(), 'nothing');
INSERT INTO [dbo].[logtable]
(
[Message]
, [ErrNr]
)
VALUES
( #ErrText
, -1
);
RAISERROR(#LogText, 11, 0) WITH NOWAIT;
END CATCH;
END;
I would like to understand what is making this transaction a "doomed"
transaction even though the XACT_ABORT is set to off.
XACT_STATE() is -1 in the catch block so the transaction is doomed.
SELECT
CASE
WHEN 1 = 0
THEN 0.0
ELSE ''
END;
Throws error
Error converting data type varchar to numeric.
"Most conversion errors" is one of the error types that Erland Sommarskog puts in the category of errors.
Batch Abortion with Rollback This is the strongest reaction SQL Server
can take to a user error. These are errors that abort execution on the
spot if there is no CATCH handler on the stack and they also roll back
any open transaction. If there is a CATCH handler, the error is
caught, but any open transaction is doomed and must be rolled back.
The behaviour is the same, no matter whether XACT_ABORT is ON or OFF.
The categorisation of error behaviours is somewhat cryptic, undocumented and not intuitive. Read his article for more details.

Commit transaction without begin transaction

I accidentally ran into a situation that I didn't put Begin Transaction at the beginning of my stored procedure and just wrote Commit Transaction as you can see below
ALTER PROCEDURE dbo.spTest
AS
BEGIN
DECLARE #MyId INT=1
BEGIN TRY
UPDATE Test
SET
-- Id -- this column value is auto-generated
CharName = 'david'
WHERE id=4
--Just to test locking behavior
WHILE(1=1)
BEGIN
SET #MyId=2;
END
COMMIT TRANSACTION
END TRY
BEGIN CATCH
ROLLBACK TRANSACTION
END CATCH
END
I expected SQL Server to give me a run time error but it didn't happen. Of course I should mention that based on my test it didn't acquire any lock on the table due to the lack of Begin Transaction but what is the point of COMMIT TRANSACTION and ROLLBACK TRANSACTION in such a condition and why didn't SQL Server raise any error?
Edit:
if i remove while block and put WaitFor Sql raise error when reaches to COMMIT TRANSACTION
ALTER PROCEDURE dbo.spTest
AS
BEGIN
UPDATE Test
SET CharName = 'david'
WHERE id=4
PRINT 'waiting for a minute '
WAITFOR DELAY '00:00:10';
COMMIT TRANSACTION
END
Now i am receiving this error
The COMMIT TRANSACTION request has no corresponding BEGIN TRANSACTION
what is the point of COMMIT TRANSACTION and ROLLBACK TRANSACTION in such a condition?
There is no point in this case
and why didn't SQL Server raise any error?
I don't see any code that would raise an error. It would help if you could explain where and why you think an error should be raised
With regards to whatever you're actually doing here;
If the purpose of this proc is to hold a transaction open, you'd need something more like this:
ALTER PROCEDURE dbo.spTest
AS
BEGIN
BEGIN TRANSACTION
UPDATE Test
SET CharName = 'david'
WHERE id=4
--Endless loop
WHILE(1=1)
BEGIN
PRINT 'waiting for a minute inside a transaction. Try something from another session'
WAITFOR DELAY '00:01';
END
-- Transaction will actually never be committed
-- Because this line will never be reached
-- because it's preceded by an endless loop
COMMIT TRANSACTION
END
The TRY / CATCH is a bit of a distraction. I've removed it.

SQL Server XACT_ABORT with exclusion

I have a larger stored procedure which utilizes several TRY/CATCH blocks in order to catch and log individual errors. I have also wrapped a transaction around the entire contents of the procedure, so as to be able to roll back the entire thing in the event of an error raised somewhere along the way (in order to prevent a lot of messy cleanup); XACT_ABORT has been enabled since it would otherwise not roll back the entire transaction.
Key component:
There is a table in my database which gets a record inserted each time this procedure is run with the results of operations and details on what went wrong.
Funny thing is happening - actually, when I finally figured out what was wrong, it was pretty obvious... the the insert statement into my log table is getting rolled back as well, hence, if I am not running this out of SSMS, I will not be able to see that this was even run, as the rollback removes all trances of activity.
Question:
Would it be possible to have the entire transaction roll back with the exception of this single insert statement? I would still want to preserve the error message which I compile during the running of the stored procedure.
Thanks so much!
~Eli
Update 6/28
Here's a code sample of what I'm looking at. Key difference between this and the samples posed by #Alex and #gameiswar is that in my case, the try/catch blocks are all nested inside the single transaction. The purpose of this is to have multiple catches (for the multiple tables), though we would the entire mess to be rolled back even if the last update failed.
SET XACT_ABORT ON;
BEGIN TRANSACTION
DECLARE #message AS VARCHAR(MAX) = '';
-- TABLE 1
BEGIN TRY
UPDATE TABLE xx
SET yy = zz
END TRY
BEGIN CATCH
SET #message = 'TABLE 1 '+ ERROR_MESSAGE();
INSERT INTO LOGTABLE
SELECT
GETDATE(),
#message
RETURN;
END CATCH
-- TABLE 2
BEGIN TRY
UPDATE TABLE sss
SET tt = xyz
END TRY
BEGIN CATCH
SET #message = 'TABLE 2 '+ ERROR_MESSAGE();
INSERT INTO LOGTABLE
SELECT
GETDATE(),
#message
RETURN;
END CATCH
COMMIT TRANSACTION
You can try something like below ,which ensures you log the operation.This takes advantage of the fact that table variables dont get rollbacked..
Psuedo code only to give you idea:
create table test1
(
id int primary key
)
create table logg
(
errmsg varchar(max)
)
declare #errmsg varchar(max)
set xact_abort on
begin try
begin tran
insert into test1
select 1
insert into test1
select 1
commit
end try
begin catch
set #errmsg=ERROR_MESSAGE()
select #errmsg as "in block"
if ##trancount>0
rollback tran
end catch
set xact_abort off
select #errmsg as "after block";
insert into logg
select #errmsg
select * from logg
OK... I was able to solve this using a combination of the great suggestions put forth by Alex and GameisWar, with the addition of the T-SQL GOTO control flow statement.
The basic ideas was to store the error message in a variable, which survives a rollback, then have the Catch send you to a FAILURE label which will do the following:
Rollback the transaction
Insert a record into the log table, using the data from the aforementioned variable
Exit the stored procedure
I also use a second GOTO statement to make sure that a successful run will skip over the FAILURE section and commit the transaction.
Below is a code snippet of what the test SQL looked like. It worked like a charm, and I have already implemented this and tested it (successfully) in our production environment.
I really appreciate all the help and input!
SET XACT_ABORT ON
DECLARE #MESSAGE VARCHAR(MAX) = '';
BEGIN TRANSACTION
BEGIN TRY
INSERT INTO TEST_TABLE VALUES ('TEST'); -- WORKS FINE
END TRY
BEGIN CATCH
SET #MESSAGE = 'ERROR - SECTION 1: ' + ERROR_MESSAGE();
GOTO FAILURE;
END CATCH
BEGIN TRY
INSERT INTO TEST_TABLE VALUES ('TEST2'); --WORKS FINE
INSERT INTO TEST_TABLE VALUES ('ANOTHER TEST'); -- ERRORS OUT, DATA WOULD BE TRUNCATED
END TRY
BEGIN CATCH
SET #MESSAGE = 'ERROR - SECTION 2: ' + ERROR_MESSAGE();
GOTO FAILURE;
END CATCH
GOTO SUCCESS;
FAILURE:
ROLLBACK
INSERT INTO LOGG SELECT #MESSAGE
RETURN;
SUCCESS:
COMMIT TRANSACTION
I don't know details but IMHO general logic can be like this.
--set XACT_ABORT ON --not include it
declare #result varchar(max) --collect details in case you need it
begin transaction
begin try
--your logic here
--if something wrong RAISERROR(...#result)
--everything OK
commit
end try
begin catch
--collect error_message() and other into #result
rollback
end catch
insert log(result) values (#result)

Transaction count after EXECUTE issue

I have written a procedure like below lines of code
ALTER PROCEDURE [dbo].[CountrySave]
(
#CountryId uniqueidentifier,
#CountryName nvarchar(max)
)
AS
begin tran
if exists (select * from Country where CountryID =#CountryId)
begin
update Country set
CountryID = #CountryId,
CountryName =#CountryName
where CountryID = #CountryId
end
else
begin
insert INTO Country(CountryID, CountryName) values
(NewID(),#CountryName)
end
It throws "Transaction count after EXECUTE indicates a mismatching number of BEGIN and COMMIT statements. Previous count = 0, current count = 1.
A transaction that was started in a MARS batch is still active at the end of the batch. The transaction is rolled back." error message when executed!!!
Please Help...
Add COMMIT TRAN
ALTER PROCEDURE [dbo].[CountrySave]
#CountryId uniqueidentifier,
#CountryName nvarchar(max)
AS
BEGIN
BEGIN TRY
BEGIN TRAN
if exists (select * from Country where CountryID =#CountryId)
begin
update Country
set CountryID = #CountryId,
CountryName =#CountryName
where CountryID = #CountryId;
end
else
begin
insert INTO Country(CountryID, CountryName)
values(NewID(),#CountryName)
end
COMMIT TRAN
END TRY
BEGIN CATCH
/* Error occured log it */
ROLLBACK
END CATCH
END
The error message is fairly clear. When you open (begin) a transaction, you will need to do something at the end of it as well.
So either you ROLLBACK the transaction (in case one of the statements within the transaction fails), or you COMMIT the transaction in order to actually implement all changes your statements made.
From MSDN:
BEGIN TRANSACTION represents a point at which the data referenced by a
connection is logically and physically consistent. If errors are
encountered, all data modifications made after the BEGIN TRANSACTION
can be rolled back to return the data to this known state of
consistency. Each transaction lasts until either it completes without
errors and COMMIT TRANSACTION is issued to make the modifications a
permanent part of the database, or errors are encountered and all
modifications are erased with a ROLLBACK TRANSACTION statement.
More information: https://msdn.microsoft.com/en-us/library/ms188929.aspx
Your Problem is that you begin a transaction but you never commit it / do a rollback.
Try this structure for your procedure, worked very well for me in the past:
CREATE PROCEDURE [dbo].SomeProc
(#Parameter INT)
AS
BEGIN
--if you want to be to only active transaction then uncomment this:
--IF ##TRANCOUNT > 0
--BEGIN
-- RAISERROR('Other Transactions are active at the moment - Please try again later',16,1)
--END
BEGIN TRANSACTION
BEGIN TRY
/*
DO SOMETHING
*/
COMMIT TRANSACTION
END TRY
BEGIN CATCH
--Custom Error could be raised here
--RAISERROR('Something bad happened when doing something',16,1)
ROLLBACK TRANSACTION
END CATCH
END

set xact_abort on and try catch together

i have a try catch block in my sp with just a insert statement in the try. the catch check error code if it is pk violation, if it is then do update. but some times i get "The current transaction cannot be committed and cannot support operations that write to the log file. Roll back the transaction.
Uncommittable transaction is detected at the end of the batch. The transaction is rolled back." so i added xact_abort on, but then i keep getting "Transaction count after EXECUTE indicates a mismatching number of BEGIN and COMMIT statements." and i found this.
http://www.ashishsheth.com/post/2009/08/14/Set-XACT_ABORT-ON-and-TryCatch-block-in-Sql-Server-2005.aspx
if this true. will my catch code not run if there is a error in my try block with xact_abort on?
It is not true, at least with SQL SERVER 2008, that SET XACT_ABORT ON will cause an error to skip the CATCH block:
Here is the code I tried using the Northwind database
SET XACT_ABORT OFF
BEGIN TRY
SELECT 1, ##TRANCOUNT
BEGIN TRAN
UPDATE [dbo].[Categories]
SET Description='BLAH'
WHERE [CategoryID]=2
SELECT 2, ##TRANCOUNT
SELECT 1/0 as whoops
COMMIT
SELECT 3, ##TRANCOUNT
END TRY
BEGIN CATCH
SELECT 'In Catch. Error occured', 4, ##TRANCOUNT
IF (XACT_STATE()) = 0
BEGIN
SELECT
N'There is no transaction'
END;
IF (XACT_STATE()) = -1
BEGIN
SELECT
N'The transaction is in an uncommittable state.' +
'Rolling back transaction.'
ROLLBACK TRANSACTION;
END;
-- Test whether the transaction is committable.
IF (XACT_STATE()) = 1
BEGIN
SELECT
N'The transaction is committable.' +
'Committing transaction.'
COMMIT TRANSACTION;
END;
END CATCH
This will, obviously, force an error when it hits the SELECT 1/0 statement. With SET XACT_ABORT OFF, when the CATCH block is reached, the value returned by the XACT_STATE() function is 1, causing the code to run which COMMITs the transaction. When SET XACT_ABORT is on, the value returned, in the CATCH block is -1 so the code which ROLLs back the transaction is executed.
This is based on:
http://msdn.microsoft.com/en-us/library/ms175976.aspx
Let me add that, in that particular scenario (try insert, if PK violation then catch and update), it would be better to use IF EXISTS (select....) to see if the row is there and put your UPDATE statement there. Put your INSERT statement in ELSE block. Much cleaner.

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