SQL Server XACT_ABORT with exclusion

Question

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

Answer 1

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)

Answer 2

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

Answer 3

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