Transaction blocks

Is there a way to continue a transaction after an error? I've got a
situation where I have a transaction open and I'm inserting data, but
some of it could fail on validation. I want to keep the good stuff,
leave out the bad, and get the speed of not having to commit every
record seperately. For a specific example, I'm importing a list of
stocks, but some symbols have changed because the list is old, so there
are invalid symbols in the list that are not found in the master list.
I want to catch the invalid ones and fix them, but still commit the
good ones. Right now I'm committing each record, but it's slow.

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"We'll do the undoable, work the unworkable, scrute the inscrutable and have a long, hard look at the ineffable to see whether it might not be effed after all"