On 04/17/2015 02:36 PM, André Somers wrote: > Bo Thorsen schreef op 17-4-2015 om 14:24: >> On 04/17/2015 02:10 PM, André Somers wrote: >>> Bo Thorsen schreef op 17-4-2015 om 13:48: >>>> On 04/17/2015 10:25 AM, Graham Labdon wrote: >>>>> Hi >>>>> My application makes use of an sqlite database that needs to be shared >>>>> amongst >>>>> multiple instantiations of the application. >>>>> Can anyone please suggest how I can implement this such that if one >>>>> instantiation of the application updates the database then any other >>>>> instantiations that are running get notified. >>>> You can't do this. There is no mechanism in sqlite to notify other >>>> applications that something has changed. You are going to have to >>>> implement an IPC system for this. >>>> >>> In fact: don't do that at all. Don't use sqlite for simultanious access >>> by several processes. We did (against recommendation of the engineers, >>> management forced a 'quick fix' to get a feature in), and we're still >>> sorry for it. You'll end up in hack-upon-hack to make it sort-of-work, >>> but it is no end of pain and sooner or later will end up in data >>> corruption in your data base. >> This contradicts the info on the sqlite website. They claim that it's >> possible to do exactly this. Interesting that you disagree. > In practice, we found that it results in problems in practise, even if > it may work in theory. Perhaps it is due to the actual sqlite, perhaps > it is due to the fact that it really is just a file and it is the > (networked) file access that is to blame in the end in our case, but the > problems are real.
According to the same documentation, it does not work if the file is on a networked file system. So if the OP use a local file system only, then it might still work. Bo Thorsen, Director, Viking Software. -- Viking Software Qt and C++ developers for hire http://www.vikingsoft.eu _______________________________________________ Interest mailing list Interest@qt-project.org http://lists.qt-project.org/mailman/listinfo/interest
