Eric B. Ridge wrote: > On Nov 15, 2005, at 12:43 PM, Bruce Momjian wrote: > > > Cristian Prieto wrote: > >> Is there any way to get the numbers of items inside a cursor? > > > > I can't see a way to do it except to do a FETCH ALL and count the > > returned rows. > > What we do, via JDBC is: > > MOVE <Integer.MAX_VALUE> IN cursor_name; > > The JDBC drivers are nice enough to return the output message from > the MOVE command, which is the number of records moved. We just keep > doing this until it returns something less than <Integer.MAX_VALUE>. > The sum of all the moves is the total number of records. Then we > just "MOVE ABSOLUTE 0 in cursor_name;" to make use of the cursor > using FETCH. > > While this does force the server to process the entire query it at > least avoids the overhead of returning all the records (which is the > point of cursors!). Yep, that works: test=> BEGIN; BEGIN test=> DECLARE xx CURSOR FOR SELECT * FROM pg_language; DECLARE CURSOR test=> MOVE 9999999 from xx; MOVE 3 Notice the "MOVE 3" returned. -- Bruce Momjian | http://candle.pha.pa.us pgman@xxxxxxxxxxxxxxxx | (610) 359-1001 + If your life is a hard drive, | 13 Roberts Road + Christ can be your backup. | Newtown Square, Pennsylvania 19073 ---------------------------(end of broadcast)--------------------------- TIP 1: if posting/reading through Usenet, please send an appropriate subscribe-nomail command to majordomo@xxxxxxxxxxxxxx so that your message can get through to the mailing list cleanly
