On Tue, 29 Jan 2002 17:45:34 +0000 (UTC), [EMAIL PROTECTED] ("Zhang,
Anna") wrote:>Thanks Peter Darley, Ross J. Reedstrom and Tom lane!! >How silly am I! Your messages reminds me. Actually I want to insert rows of >contact_discard table which are not exists in contact table to contact table >(some duplicates in two tables), first I run > >insert into contact >select * from contact_discard a >where not exists ( select 1 from contact b where b.contacthandle = >a.contacthandle); > >It seems takes forever, I killed it after hours(note: contact table has 4 >indexes). Then I tried to figure out how many rows that are not duplicated. >Now my problem turns to insert performance, in oracle it takes only a few >minues. > >Thanks! > >Anna Zhang > With millions of rows, you also might want to create a temporary (real) table with just the select statement, then drop ALL the indexes on contact, do the update, then recreate the indexes. Bob Hairgrove [EMAIL PROTECTED] ---------------------------(end of broadcast)--------------------------- TIP 3: if posting/reading through Usenet, please send an appropriate subscribe-nomail command to [EMAIL PROTECTED] so that your message can get through to the mailing list cleanly
