From oracle-l-bounce@freelists.org Tue Jun 8 08:34:52 2004 Return-Path: Received: from air189.startdedicated.com (root@localhost) by orafaq.com (8.11.6/8.11.6) with ESMTP id i58DYRq29457 for ; Tue, 8 Jun 2004 08:34:37 -0500 X-ClientAddr: 206.53.239.180 Received: from turing.freelists.org (freelists-180.iquest.net [206.53.239.180]) by air189.startdedicated.com (8.11.6/8.11.6) with ESMTP id i58DYH629413 for ; Tue, 8 Jun 2004 08:34:27 -0500 Received: from localhost (localhost [127.0.0.1]) by turing.freelists.org (Avenir Technologies Mail Multiplex) with ESMTP id A889672CA6A; Tue, 8 Jun 2004 08:20:04 -0500 (EST) Received: from turing.freelists.org ([127.0.0.1]) by localhost (turing [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 30599-16; Tue, 8 Jun 2004 08:20:04 -0500 (EST) Received: from turing (localhost [127.0.0.1]) by turing.freelists.org (Avenir Technologies Mail Multiplex) with ESMTP id 0344172CA2E; Tue, 8 Jun 2004 08:19:33 -0500 (EST) Received: with ECARTIS (v1.0.0; list oracle-l); Tue, 08 Jun 2004 08:17:58 -0500 (EST) X-Original-To: oracle-l@freelists.org Delivered-To: oracle-l@freelists.org Received: from localhost (localhost [127.0.0.1]) by turing.freelists.org (Avenir Technologies Mail Multiplex) with ESMTP id E06FE72C8B1 for ; Tue, 8 Jun 2004 08:17:57 -0500 (EST) Received: from turing.freelists.org ([127.0.0.1]) by localhost (turing [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 29136-55 for ; Tue, 8 Jun 2004 08:17:57 -0500 (EST) Received: from corporate.LifeTouch.com (corporate.LifeTouch.com [63.71.63.1]) by turing.freelists.org (Avenir Technologies Mail Multiplex) with SMTP id 6AB3272C85B for ; Tue, 8 Jun 2004 08:17:57 -0500 (EST) Received: from no.name.available by corporate.LifeTouch.com via smtpd (for freelists-180.iquest.net [206.53.239.180]) with SMTP; 8 Jun 2004 13:39:46 UT Received: (private information removed) Message-ID: <0186754BC82DD511B5C600B0D0AAC4D607B0076C@EXCHMN3> From: DENNIS WILLIAMS To: "'oracle-l@freelists.org'" Subject: RE: Cats, Pigeons and Open Cursors Date: Tue, 8 Jun 2004 08:33:58 -0500 MIME-Version: 1.0 X-Mailer: Internet Mail Service (5.5.2657.72) Content-Type: text/plain; charset="iso-8859-1" X-Virus-Scanned: by amavisd-new at freelists.org X-archive-position: 2239 X-ecartis-version: Ecartis v1.0.0 Sender: oracle-l-bounce@freelists.org Errors-To: oracle-l-bounce@freelists.org X-original-sender: DWILLIAMS@LIFETOUCH.COM Precedence: normal Reply-To: oracle-l@freelists.org X-list: oracle-l X-Virus-Scanned: by amavisd-new at freelists.org Justin I agree with you 99%. My only quibble is with your statement "relatively easy to walk through the code". I won't pass myself off as a Java expert, but just want to point out that OOP like Java have a much more complex execution path than the older procedural languages most of us are familiar with. Transaction boundaries become very difficult to delineate, especially with event-driven GUI interfaces. Then there are things like J2EE that can handle database access automagically. Part of the value of modern development environments like Java is to utilize code others have written rather than writing every line of code yourself like most of us did in the older languages. I'm not denying that it may be necessary in some situations for the execution path to be traced in detail to determine the problem, just that the "relatively easy" may not be quite the case. Dennis Williams DBA Lifetouch, Inc. dwilliams@lifetouch.com -----Original Message----- From: oracle-l-bounce@freelists.org [mailto:oracle-l-bounce@freelists.org]On Behalf Of Justin Cave Sent: Tuesday, June 08, 2004 4:57 AM To: oracle-l@freelists.org Subject: RE: Cats, Pigeons and Open Cursors I think you are running into a fundamental problem. Once you return a cursor to the Java application, the Java application owns it. Oracle doesn't generally allow you to come along and kill things owned by another session. The only ways I'm aware of to close the cursor would be to do so in the Java application or to kill the entire session from PL/SQL. If your Java developers are moderately competent, it should be relatively easy to walk through the code and ensure that all the cursors are closed by the appropriate exception block. If there are a few corner cases where cursors are not closed, you can cycle connections from the connection pool or close long-open connections from PL/SQL. The former option will probably cause your Java application fewer problems. Justin Cave Distributed Database Consulting, Inc. http://www.ddbcinc.com/askDDBC -----Original Message----- From: oracle-l-bounce@freelists.org [mailto:oracle-l-bounce@freelists.org] On Behalf Of Piet de Visser Sent: Tuesday, June 08, 2004 3:31 AM To: oracle-l@freelists.org Subject: Cats, Pigeons and Open Cursors List, We have a nice problem between Java and Pl/sql, and since PL/sql is slightly out of my comfort zone, I'm submitting it to the list (fairly sure we are not the first to stumble on this). A procedure is used to open an number of ref-cursors and pass them back to java as out-parameters. Which cursors are opened varies and depends on in-parameters. When Java is done using the cursors, it Should close all the opened cursors. Sometimes the closing is skipped or forgotten, and the nr-open-cursors increases rapidly. Since connections are rarely closed, but rather re-used, the db runs out of open cursors. Given the fact that we do not quite trust the Java code to always close all cursors, we would like to build a sure-fire way in Pl/sql to close all previously opened cursors. First suggestion was to create another procedure that checks all cursors using ISOPEN%cursor123 and closes them. This doesn't work because REF-cursors can apparently not be declared outside of functions or procedures. Question: - Is there a way to refer to ref-cursors inside a package, and to have a list if ref-cursors closed conditionally by using : IF refcur1%ISOPEN THEN CLOSE refcur1 ; END IF; ? More precisely, we want the package to keep track of all cursors it has opened (we can keep a list, no problem if that requires some extra code). We then want the same procedure or another procedure to go in, read the list of open cursors, an close any that are still open. Is this feasible ? Suggestions anyone ? Regards, PdV -- Tribute to All quotes on Developers, Cats, -- -- Statues and Pigeons. It is all True. -- -- Disclaimers are like Art -- -- You can read in them whatever you want -- This e-mail and any attachment is for authorised use by the intended recipient(s) only. It may contain proprietary material, confidential information and/or be subject to legal privilege. It should not be copied, disclosed to, retained or used by, any other party. If you are not an intended recipient then please promptly delete this e-mail and any attachment and all copies and inform the sender. Thank you. ---------------------------------------------------------------- Please see the official ORACLE-L FAQ: http://www.orafaq.com ---------------------------------------------------------------- To unsubscribe send email to: oracle-l-request@freelists.org put 'unsubscribe' in the subject line. -- Archives are at http://www.freelists.org/archives/oracle-l/ FAQ is at http://www.freelists.org/help/fom-serve/cache/1.html ----------------------------------------------------------------- ---------------------------------------------------------------- Please see the official ORACLE-L FAQ: http://www.orafaq.com ---------------------------------------------------------------- To unsubscribe send email to: oracle-l-request@freelists.org put 'unsubscribe' in the subject line. -- Archives are at http://www.freelists.org/archives/oracle-l/ FAQ is at http://www.freelists.org/help/fom-serve/cache/1.html ----------------------------------------------------------------- ---------------------------------------------------------------- Please see the official ORACLE-L FAQ: http://www.orafaq.com ---------------------------------------------------------------- To unsubscribe send email to: oracle-l-request@freelists.org put 'unsubscribe' in the subject line. -- Archives are at http://www.freelists.org/archives/oracle-l/ FAQ is at http://www.freelists.org/help/fom-serve/cache/1.html -----------------------------------------------------------------