I think I might be getting confused on this subject as well. Does this mean that SQLite 3.x can NOT process multiple inserts/updates within one transaction if it is working on the same table?
ie Below would return "database table is locked"? BEGIN TRANSACTION SELECT * from table1 WHERE col > x UPDATE table1 SET col = ... INSERT INTO table1 .... COMMIT TRANSACTION Nick -----Original Message----- From: Thomas Briggs [mailto:[EMAIL PROTECTED] Sent: 12 May 2005 16:11 To: sqlite-users@sqlite.org Subject: RE: [sqlite] database table is locked *** WARNING *** This mail has originated outside your organization, either from an external partner or the Global Internet. Keep this in mind if you answer this message. Aha! Now I understand what's going on. I have been completely missing the fact that everyone is trying to update the same table they're reading from. I know that's obvious to you guys, but I completely missed that subtle fact. Everything makes sense now. Thanks for your patience. :) -Tom > -----Original Message----- > From: Martin Engelschalk [mailto:[EMAIL PROTECTED] > Sent: Thursday, May 12, 2005 9:53 AM > To: sqlite-users@sqlite.org > Subject: Re: [sqlite] database table is locked > > @Thomas Briggs, Jay Sprenckle > > I use the C Api described at http://www.sqlite.org/capi3ref.html. > > My code seemed to work with sqlite 3.0.7, but I cannot be too sure > because my project is in development. It would take some time > to check > with 3.0.7 > > My code worked roughly like this: > I created an update - Statement using compile(). > I created a query (simple select from one table) using compile() and > fetched the data using sqlite3_step() > When i found a record i needed to update, i bound 2 Variables using > sqlite3_bind_text() to the update statement, one of which was the > integer primary key. > The sqlite3_exec() failed with "database table is locked". > > This is a different thing to "database locked", i think. > > Martin > > Thomas Briggs schrieb: > > > This question seems to come up often, and I'm still confused as to > >what problems people are having. What APIs are you using to perform > >these steps? In particular, when you want to update a row, are you > >using a prepared query that is executed multiple times, or are you > >creating an SQL statement and executing that with > sqlite3_exec? Are you > >using 2.8 or 3.x? Maybe the confusion on my part is due to different > >database versions. > > > > I'm confused as to why executing a query would lock the database. > >The only thing I can think of is that the query required a > temp table, > >and the creation of that temp table led to the database being locked. > >The entire many readers/single writer concept makes no sense if > >executing any query locks the whole database. > > > > -Tom > > > > > > > >>-----Original Message----- > >>From: Thomas Fjellstrom [mailto:[EMAIL PROTECTED] > >>Sent: Thursday, May 12, 2005 7:10 AM > >>To: sqlite-users@sqlite.org > >>Subject: Re: [sqlite] database table is locked > >> > >>On May 12, 2005 04:59 am, Martin Engelschalk wrote: > >> > >> > >>>Hello, > >>> > >>>i open cursor on a table and retrieve rows from it. > >>>For every row i decide whether to update it. However, when > >>> > >>> > >>executing > >> > >> > >>>the update I get the error "database table is locked". > >>>My application is the only one working on the table. > >>>Is it illegal to update a table while selecting from it or > >>> > >>> > >>am i doing > >> > >> > >>>somethin wrong? > >>> > >>>Thanks, > >>>Martin > >>> > >>> > >>Yup. you'll have to scan for updates to make, then after the > >>scan, make the > >>updates. > >> > >>-- > >>Thomas Fjellstrom > >>[EMAIL PROTECTED] > >> > >> > >> > ******************************************************************** This email and any attachments are confidential to the intended recipient and may also be privileged. If you are not the intended recipient please delete it from your system and notify the sender. You should not copy it or use it for any purpose nor disclose or distribute its contents to any other person. ********************************************************************
