The following bug has been logged online: Bug reference: 3824 Logged by: Gregor Roessle Email address: g.roessle@osram.de PostgreSQL version: 8.2.5 Operating system: Linux - Kernel 2.4.33 Description: Query hangs when result set empty using sort and limit Details: The Server hangs when executing a query like this: select * from messwerte where pknr = 28315178 and isproducing = 't' order by timestamp desc limit 1; leaving out the "order by" and "limit" the result set is empty and returned in 32ms from the remote installed server (i.e. very fast). Adding the "order by" causes no trouble, also does "limit". But if i add _both_ - "limit" and "order by" as shown above the query hangs. I personally consider this a bug. But maybe my query is not sophisticated enough... ---------------------------(end of broadcast)--------------------------- TIP 6: explain analyze is your friend

"Gregor Roessle" <g.roessle@osram.de> writes: > The Server hangs when executing a query like this: > select * from messwerte where pknr = 28315178 and isproducing = 't' order by > timestamp desc limit 1; I seriously doubt that it's hung. Takes a long time, maybe so. Is it trying to use an indexscan on timestamp to substitute for a sort step? regards, tom lane ---------------------------(end of broadcast)--------------------------- TIP 3: Have you checked our extensive FAQ? http://www.postgresql.org/docs/faq