Path: text.usenetserver.com!out03b.usenetserver.com!news.usenetserver.com!in02.usenetserver.com!news.usenetserver.com!postnews.google.com!e10g2000prf.googlegroups.com!not-for-mail From: Steve Howard Newsgroups: comp.databases.oracle.server Subject: Re: (Java) Synchronizing multiple app servers through Oracle Date: Wed, 12 Dec 2007 18:16:18 -0800 (PST) Organization: http://groups.google.com Lines: 48 Message-ID: References: <905e4f99-e729-4d84-90e8-378a997357cb@b40g2000prf.googlegroups.com> <891f1536-701e-4046-8769-96c5662ec7ed@b40g2000prf.googlegroups.com> NNTP-Posting-Host: 75.118.5.89 Mime-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit X-Trace: posting.google.com 1197512178 4999 127.0.0.1 (13 Dec 2007 02:16:18 GMT) X-Complaints-To: groups-abuse@google.com NNTP-Posting-Date: Thu, 13 Dec 2007 02:16:18 +0000 (UTC) Complaints-To: groups-abuse@google.com Injection-Info: e10g2000prf.googlegroups.com; posting-host=75.118.5.89; posting-account=wtlN5gkAAAAVr064jxzGl8R72LkgvhF6 User-Agent: G2/1.0 X-HTTP-UserAgent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.8.1.11) Gecko/20071127 Firefox/2.0.0.11,gzip(gfe),gzip(gfe) Xref: usenetserver.com comp.databases.oracle.server:439017 X-Received-Date: Wed, 12 Dec 2007 21:16:18 EST (text.usenetserver.com) On Dec 12, 9:04 pm, chrism...@gmail.com wrote: > On Dec 12, 8:33 pm, Steve Howard wrote: > > > > > On Dec 12, 8:10 pm, chrism...@gmail.com wrote: > > > > What is the recommended way for using an Oracle database to > > > synchronize multiple app servers? When I speak of synchronizing, I'm > > > referring to the Java use of the word, where you can lock a section of > > > code so other threads don't access that section at the same time. > > > > I have multiple app servers that each need exclusive access to the > > > database for a certain operation. Does Oracle have a semaphore > > > utility that is available to apps? I know I could hack it by doing a > > > select for update on a dummy table with 1 row, but I was hoping Oracle > > > had something more elegant to use. > > > > Thanks. > > > Hi, > > > Oracle locks rows by default (it doesn't matter if it's java, C#, VB, > > C, SQL*Plus, etc.), but I don't know what you mean "exclusive access > > to the database for a certain operation". If you have a need for more > > sophisticated application locking, look into the procedures in the > > dbms_lock package at tahiti.oracle.com > > > HTH, > > > Steve > > dbms_lock sounds like exactly what I'm looking for. It doesn't appear > to be part of Oracle 10g (the version I'm using). Is it downloadable > from the Oracle web site? I didn't find it my first try. > > Thanks. AFAIK, dbms_lock is part of the standard installation. In SQL*PLus, type desribe dbms_lock to see if it is already installed. If it not in your database for whatever reason, it can be installed by running dbmslock.sql under $ORACLE_HOME/rdbms/admin HTH, Steve