2009/11/18 Lee Hachadoorian <[email protected]>: > On Wed, Nov 18, 2009 at 2:30 PM, Pavel Stehule <[email protected]> > wrote: >> yes, and don't use 20%. >> >> select * from foo order by somecol limit (select (count(*)*0.2)::int from >> foo) >> >> Regards >> Pavel > > Is this faster on a large table? Because (select (count(*)*20/100)) worked > fine. >
this is +/- same - 20/100 is maybe about 0.000001% faster - you don't need one float to query cast, but this operation is only one pqr query. The problem is two full scan of table. Pavel -- Sent via pgsql-sql mailing list ([email protected]) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-sql
