#1 What version of Sqlite and Windows client/server are you using? #2 What language is your application written in? #3 Are all your databases on the same share mount point? #4 Is your share mounted as a drive letter? Michael D. Black Senior Scientist Advanced Analytics Directorate Northrop Grumman Information Systems
________________________________ From: [email protected] on behalf of Serena Lien Sent: Sat 11/6/2010 3:08 AM To: General Discussion of SQLite Database Subject: EXTERNAL:Re: [sqlite] RESOLVED: unable to open database file/Disc I/O error No, I didn't explain correctly. My application is not open overnight, only the computer. So I do not have any database connections open at all, they are not going stale. In the morning, I start the application, and it opens some databases in readwrite mode and executes statements without errors. It opened some databases in readonly mode and executes statements, these return SQLITE_BUSY errors, nothing else is using the databases. Therefore there is nothing wrong with the network connection as it has already accessed networked databases before my errors occur. I can only conclude it must be a bug with locking using the readonly flag - either sqlite or something vista OS specific going wrong. cheers Serena. On Fri, Nov 5, 2010 at 10:52 PM, H. Phil Duby <[email protected]>wrote: > On Fri, Nov 5, 2010 at 3:25 AM, Serena Lien <[email protected]> wrote: > > > > I would like to inform the group that I managed to resolve the issue with > a > > workaround. I am not sure if this is a bug in vista or whether there > might > > in fact be some slight issue with sqlite... > > > > The problem seems to be hardware and software related, and occurs for me > > when my application is running on Windows Vista and is opening a database > on > > a networked drive (running Windows Small Business Server 2008) with the > > read-only flag. Running sql queries on the database after this will > > return SQLITE_BUSY when no one is using the database. Once the > application > > is closed and restarted the error does not re-occur. This is highly > > reproducible once per day (in the morning after the machine has powered > down > > the screen only, it doesn't go to sleep). > > Given that sequence / timing, I *suspect* this is actually caused by > the network connection 'timing out'. Your application thinks it has > the database file open, but SBS has _decided_ that the connection is > stale, and closed it. I do not know why your symptoms would only show > up for read only connections. You might be able to continue after the > error, by having the application close and reopen / reconnect to the > database file. You might get an error doing a normal close as well, > because SBS thinks it is already closed. > > When your Vista system powers down the screen, it may *also* be > powering down the [wired or wireless] network card, which could > trigger SBS to close the read only connection. > > > Removing that flag and making sure I only open databases in read-write > mode > > has resolved the problem. I have tested this thoroughly over a period of > > many days. > > > > As I said I'm not sure if this is an sqlite bug or not (and I'm sure very > > difficult to reproduce) but I'm writing this in case anyone else has the > > same problem in the hope it helps them. > > > > cheers Serena > -- > Phil > _______________________________________________ > sqlite-users mailing list > [email protected] > http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users > _______________________________________________ sqlite-users mailing list [email protected] http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
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