Tom Lane wrote: > Bruce Momjian <[EMAIL PROTECTED]> writes: > > Tom Lane wrote: > >> Bruce Momjian <[EMAIL PROTECTED]> writes: > > Seems we have a problem with pooled connections and WITH HOLD cursors. > > We have code to reset transaction state and variables via RESET ALL, but > > how do we remove WITH HOLD cursors when we pass a connection to a new > > client? > >> > >> Prepared statements would be just as much of a problem. I think the > >> correct answer is simply "don't use those features in a pooled > >> environment". > > > Yuck. I can't think of any other option. The pooled connections are > > all the same user, so there isn't any permission issue here. > > Well, one answer for cursors would be to offer a "CLOSE ALL" sort of > command. I'm not sure it's worth the trouble though. I can't really > visualize a reason to use held cursors in a pooled environment. A held > cursor is pointless unless you intend to use it for more than one > transaction, and in a pooled environment that would be difficult, no? > When you commit one transaction and start another, you might not have > the same connection anymore.
I am thinking more of someone using WITH HOLD cursors and getting disconnected before being able to close it. > Rod's right that sharing prepared statements among all users of a pooled > connection might be interesting. However, I wonder whether anyone would > actually use a "list prepared statements" feature to implement it. > Seems like checking that way would just be a wasted roundtrip for most > transactions. I'd be inclined to set up the app so that all the > required statements are prepared the moment it opens a new connection, > and the pool users just assume the statements are available. What would be interesting is a CREATE OR REPLACE functionality for prepared cursors, where you could ask for it to be prepared, but if it already existed, it would do nothing, or something like that. -- Bruce Momjian | http://candle.pha.pa.us [EMAIL PROTECTED] | (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 6: Have you searched our list archives? http://archives.postgresql.org
