Using BEGIN TRAN for a SELECT statement
I have inherited a number of stored procedures that are using explicit transactions and structured error handling.
I have had to review the procs due to deadlocks occurring and have found that many of them are SELECT statements.
The syntax is like this:
BEGIN TRAN
BEGIN TRY
SELECT ####
END TRY
BEGIN CATCH
IF @@TRANCOUNT >0
BEGIN
ROLLBACK TRAN
INSERT ErrorLog
XXXXXX
END CATCH
IF @@TRANCOUNT > 0
BEGIN
COMMIT TRAN
END
It is very obvious that there is no purpose for explicit transactions in the select, but I am wondering if this could be a factor in the deadlocks. From what I tested using BEGIN TRAN for a select still only uses a shared lock.
Is it possible that this is a factor in the deadlocks?
David Dye My Blog
There is no need of explicit transaction in select statement what exactly would you want to rollback, nothing. Although you might use error handling depending on complexity of select involved.
Plus drawbacks is locks would be held for longer duration which MIGHT provide some help in deadlock
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BAuser575682 wrote:
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