On Wednesday 22 March 2006 13:11, Tom Lane wrote: > Peter Eisentraut <[EMAIL PROTECTED]> writes: > > How does one get at the missing fields. The only way I know is > > selecting from the sequence, but how does one work this into this > > query? Somehow it seems that these things should be stored in a real > > system catalog. > > Yeah. I've occasionally toyed with the idea that sequences should be > rows in a single catalog instead of independent tables as they are now. > This would make for a much smaller disk footprint (with consequent I/O > savings) and would solve problems like the one you have. Unfortunately > the backward-compatibility issues seem a bit daunting :-(. It's > probably not completely impossible, but how do we preserve the existing > behavior that you can "SELECT * FROM seqname" and get the parameters? > > Ideally I'd like > SELECT * FROM seqname; -- gets params of one sequence > SELECT * FROM pg_sequence; -- gets params of all sequences > > One possible kluge is to make all the sequences be child tables of a > pg_sequence catalog that exists only to be their inheritance parent. > This seems pretty ugly from a performance point of view though. > Selecting from pg_sequence would be really expensive if you have a lot > of sequences, and there wouldn't be any opportunity for reducing the > disk footprint. > > (Thinks a bit...) Maybe it would work for pg_sequence to be a real > catalog with a row per sequence, and we also create a view named after > the sequence that simply selects from pg_sequence with an appropriate > WHERE condition.
I'd think that would be a workable solution, with documentation notes that this will be deprecated in favor of information_schema in an upcoming release ? > > Plan C would be to say that we don't need to preserve "SELECT * FROM > seqname", but I'll bet there would be some hollering. ? > > regards, tom lane > > ---------------------------(end of broadcast)--------------------------- > TIP 6: explain analyze is your friend -- Darcy Buskermolen Wavefire Technologies Corp. http://www.wavefire.com ph: 250.717.0200 fx: 250.763.1759 ---------------------------(end of broadcast)--------------------------- TIP 6: explain analyze is your friend
