Martijn van Oosterhout <kleptog@svana.org> writes:
> How do other database deal with this? Either they nest BEGIN/COMMIT or
> they probably throw an error without aborting the transaction, which is
> pretty much what we do. Is there a database that actually aborts a
> whole transaction just for an extraneous begin?
Probably not. The SQL99 spec does say (in describing START TRANSACTION,
which is the standard spelling of BEGIN)
1) If a <start transaction statement> statement is executed when an SQL-transaction is currently
active,then an exception condition is raised: invalid transaction state - active SQL-transaction.
*However*, they are almost certainly expecting that that condition only
causes the START command to be ignored; not that it should bounce the
whole transaction. So I think the argument that this is required by
the spec is a bit off base.
regards, tom lane