Re: Transaction wrapper

Florian Weimer wrote:
> Is there are ready-to-use transaction wrapper for DBD:Pg?  I'm looking
> for somehting which can be used like this:

Oh, absolutely there is.

See http://search.cpan.org/dist/DBIx-Connector/ which David Wheeler put out a 
few years ago.  See the txn() method.

Besides doing exactly what you want (it also does the begin_work/commit for 
you), DBIx::Connector also makes it easier to write things that behave correctly 
in different contexts such as persisting DBI connections in Apache versus 
non-persisting ones in scripts.  And it is DBMS-portable.

The module takes care of just a small number of things that are tricky to get 
right and that most people don't want to have to do themselves, and it otherwise 
stays out of your way.

-- Darren Duncan

> 
>     my $connect_args = [$data_source, $username, $auth, \%attr];
>     transact $connect_args, sub {
>       my ($dbh) = @_;
>       $dbh->begin_work;
>       ...
>       $dbh->commit;
>     };
> 
> The transact subroutine should abort the transaction if the passed sub
> dies.  For certain exceptions, the sub should be called again to retry
> the transaction.  The database handle should be cached.
> 
> This is somewhat PostgreSQL-specific because there are three cases:
> permanent errors (such as SQL syntax errors, or non-SQL exceptions),
> transient errors which will go away when the transaction is retried
> within the same connection (such as serialization failures and certain
> types of UNIQUE constraint violations), and errors which will likely go
> away when the transaction is retried with a fresh connection (due to
> server restart, for example).
> 
> This is not very difficult to write as such, but getting the error code
> list right is a bit delicate.
> 

• Transaction wrapper by Florian Weimer
• Re: Transaction wrapper by Rainer Weikusat
• Re: Transaction wrapper by Darren Duncan
• Re: Transaction wrapper by Florian Weimer