Re: Commit every N rows in PL/pgsql

Chris Browne <cbbrowne(at)acm(dot)org> writes:
> len(dot)walter(at)gmail(dot)com (Len Walter) writes:
>> I need to populate a new column in a Postgres 8.3 table. The SQL would be something like "update t set col_c = col_a +
>> col_b". Unfortunately, this table has 110 million rows, so running that query runs out of memory.
>
> Unnecessary. On Oracle, the typical scenario is "ORA-1562 FAILED TO
> EXTEND ROLLBACK SEGMENT."
>
> PostgreSQL doesn't have a rollback segment, so there's nothing to run
> out of here. Where Oracle would tend to encourage you to keep your
> transactions rather small, PostgreSQL doesn't require you to care about
> that.
>
> Big transactions, on PostgreSQL, are really no big deal.

Unless, of course, there's a trigger on that table. In which case
it's pretty likely that you'd want to suppress the trigger...
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