On Wed, 24 Apr 2013 11:19:32 +0200 "J Trahair" <[email protected]> wrote:
> Thanks for the replies so far. > > I've been trying to get the database to lock - I am using a program I > developed which runs on 2 of my computers but connected to the same SQLite > database: > > mstrSQL = "PRAGMA locking_mode = EXCLUSIVE;BEGIN EXCLUSIVE;UPDATE > Utilities SET OwnersName = '" & Date.Now & "' WHERE RecNo = 1;COMMIT;" I found, by bad experiences, that it's better to have a program/process that owns the database and others send petitions to it, something like a client-server, than have an always growing number of process/programs that works with the same db file. If some of them are remote process, its even worse. You can think in a kitchen were lot of cookers work on one meal, using one knive, one fire, one pot, one... sooner or later the chaos arrives and the meal is carbonized. > > On running this code (VB.Net), the record updates successfully, the message > 'Done!" displays, no error message - but the same program on another > computer pointing to the same database across the network is still able to > open the database and run the program. > Do you close the db connection after the commit? Or reset locking mode to normal? See recent posts about locking db files using nfs. > I have missed something - but what is it? Thanks for your help. > > Jonathan > > > On 17 April 2013 14:39, J Trahair <[email protected]> wrote: > > Hi everyone > > > > Can my application lock the database for its own exclusive use at the > beginning of a series of INSERTs UPDATEs and SELECTs, then unlock it again > afterwards? I've read about the five locking states (unlocked, shared, etc.) > but I assume the dll handles all that at INSERT or UPDATE time. I'm looking > for a way to ensure other users aren't allowed to write to the database > during this quarter-second period. > > http://www.sqlite.org/lang_transaction.html > BEGIN EXCLUSIVE > > > > > Thanks in advance. > > > > Jonathan Trahair > > Regards, > Simon > _______________________________________________ > sqlite-users mailing list > [email protected] > http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users --- --- Eduardo Morras <[email protected]> _______________________________________________ sqlite-users mailing list [email protected] http://sqlite.org:8080/cgi-bin/mailman/listinfo/sqlite-users
