Re: VLDB Features

Neil Conway <neilc@samurai.com> writes:
> By modifying COPY: COPY IGNORE ERRORS or some such would instruct COPY
> to drop (and log) rows that contain malformed data. That is, rows with
> too many or too few columns, rows that result in constraint violations,
> and rows containing columns where the data type's input function raises
> an error. The last case is the only thing that would be a bit tricky to
> implement, I think: you could use PG_TRY() around the InputFunctionCall,
> but I guess you'd need a subtransaction to ensure that you reset your
> state correctly after catching an error.

Yeah.  It's the subtransaction per row that's daunting --- not only the
cycles spent for that, but the ensuing limitation to 4G rows imported
per COPY.

If we could somehow only do a subtransaction per failure, things would
be much better, but I don't see how.
        regards, tom lane