Ok, I appreciate the information! Thanks,
Jerry -----Original Message----- From: sqlite-users-boun...@sqlite.org [mailto:sqlite-users-boun...@sqlite.org] On Behalf Of Richard Hipp Sent: Tuesday, May 08, 2012 8:20 PM To: General Discussion of SQLite Database Subject: Re: [sqlite] SQLite via TCL Question On Tue, May 8, 2012 at 7:40 PM, Tilsley, Jerry M. <jmtils...@st-claire.org>wrote: > I have set the timeout now and will monitor this change, on the note > of using WAL I do have a question. The database is accessed by SQLite > 3.6.4 from a vendor's application, but on command-line I used 3.7.9; > am I asking from trouble? Should I go through the effort to force the > vendor's application to use the 3.7.9 version when talking to my custom DB? > SQLite 3.6.4 is unable to read a WAL database. I recommend you update the database in the vendors application. > > -----Original Message----- > From: sqlite-users-boun...@sqlite.org [mailto: > sqlite-users-boun...@sqlite.org] On Behalf Of Duquette, William H > (318K) > Sent: Tuesday, May 08, 2012 5:13 PM > To: General Discussion of SQLite Database > Subject: Re: [sqlite] SQLite via TCL Question > > > > On 5/8/12 1:51 PM, "Tilsley, Jerry M." <jmtils...@st-claire.org> wrote: > > >This is probably a newbie question so please bear with me. I'm > >accessing a SQLite database through TCL and periodically I get a > "Database Locked" > >error. This is a multi-thread process that writes to the DB, do I > >need to enable WAL for this, if so, do I do this from the TCL side or > >the command-line side? > > If only one thread is writing, then using WAL should do the trick; the > other threads can read while the writer is writing. If multiple > threads are writing, that's a whole different issue, and WAL (while it > might still be a good idea) won't prevent the problem. > > You enable WAL mode using the "journal_mode" pragma; once it's set > it's persistent. So you'd want to set it when creating a new > database, wherever you do that; on an existing database, wherever you > like. See sqlite.org/wal/html. > > If you've gotten multiple writers you can set a lock timeout using the > database handle's "timeout" subcommand; it defaults to 0.0. You'll > still need to handle lock errors, though; a timeout isn't a guarantee. > > Will > > > -- > Will Duquette -- william.h.duque...@jpl.nasa.gov Athena Development > Lead > -- Jet Propulsion Laboratory "It's amazing what you can do with the > right tools." > > > > > > > > >________________________________ > > > >Disclaimer**** > >This email is confidential and intended solely for the use of the > >individual to whom it is addressed. Any views or opinions presented > >are solely those of the author and do not necessarily represent those of St. > >Claire Regional Medical Center. If you are not the intended > >recipient, be advised that you have received this email in error and > >that any use, dissemination, forwarding, printing or copying of the > >email is strictly prohibited. If you received this email in error please > >notify the St. > >Claire Regional Helpdesk by telephone at 606-783-6565. > >_______________________________________________ > >sqlite-users mailing list > >sqlite-users@sqlite.org > >http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users > > _______________________________________________ > sqlite-users mailing list > sqlite-users@sqlite.org > http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users > > ________________________________ > > Disclaimer**** > This email is confidential and intended solely for the use of the > individual to whom it is addressed. Any views or opinions presented > are solely those of the author and do not necessarily represent those of St. > Claire Regional Medical Center. If you are not the intended recipient, > be advised that you have received this email in error and that any > use, dissemination, forwarding, printing or copying of the email is > strictly prohibited. If you received this email in error please notify the St. > Claire Regional Helpdesk by telephone at 606-783-6565. > _______________________________________________ > sqlite-users mailing list > sqlite-users@sqlite.org > http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users > -- D. Richard Hipp d...@sqlite.org _______________________________________________ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users ________________________________ Disclaimer**** This email is confidential and intended solely for the use of the individual to whom it is addressed. Any views or opinions presented are solely those of the author and do not necessarily represent those of St. Claire Regional Medical Center. If you are not the intended recipient, be advised that you have received this email in error and that any use, dissemination, forwarding, printing or copying of the email is strictly prohibited. If you received this email in error please notify the St. Claire Regional Helpdesk by telephone at 606-783-6565. _______________________________________________ sqlite-users mailing list sqlite-users@sqlite.org http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
