On Dec 15, 2010, at 4:39 AM, Simon Riggs wrote: > On Wed, 2010-12-15 at 10:54 +0100, Csaba Nagy wrote: >> On Tue, 2010-12-14 at 14:36 -0500, Robert Haas wrote: >>>> Well, you have to do that for DROP TABLE as well, and I don't see any >>>> way around doing it for REPLACE WITH. >>> >>> Sure, but in Simon's proposal you can load the data FIRST and then >>> take a lock just long enough to do the swap. That's very different >>> from needing to hold the lock during the whole data load. >> >> Except Simon's original proposal has this line in it: >> >> * "new_table" is TRUNCATEd. >> >> I guess Simon mixed up "new_table" and "old_table", and the one which >> should get truncated is the replaced one and not the replacement, >> otherwise it doesn't make sense to me. > > What I meant was... > > REPLACE TABLE target WITH source; > > * target's old rows are discarded > * target's new rows are all of the rows from "source". > * source is then truncated, so ends up empty > > Perhaps a more useful definition would be > > EXCHANGE TABLE target WITH source; > > which just swaps the heap and indexes of each table. > You can then use TRUNCATE if you want to actually destroy data.
Are there any considerations with toast tables and the inline line pointers for toasted tuples? Regards, David -- David Christensen End Point Corporation da...@endpoint.com -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
