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POHow to check lock status and unlock if necessary for Database on Blackberry?
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copied!<p>Since I've started developing my Blackberry app, the biggest problems I've encountered all had to do with SQLite Databases.</p> <p>Right now I'm putting my app through a stress test, and when problems pop up I address them by printing out statuses to the console and taking care of things line by line. Right now (after mashing buttons on my app) I received a "Database is locked" error and I'm not sure what to do.</p> <p>It seems that once the database is locked it's locked for good until it is unlocked........ my question is how can I unlock it?? First of all, how can I check to see if it's locked??</p> <p>I'm sure our users won't be mashing buttons like I did, but you never know. I want to account for every possible scenario.</p> <p>Thanks</p> <p><em>EDIT: This is what happens in my application..... When I launch it starts a thread, this thread performs a cleanup on one of my tables based on how old certain pieces of data are (uses DELETE). The thread then continues to get a USER object from my DB (read only), it then uses this USER object as a parameter to call a web service. The data retrieved from the web service is INSERTED into my database. (It's a little more complex than that as a few read/write operations are performed at this time. After that, the thread fires a callback method to update my UI.</em></p> <p><em>This all works fine. I can exit the app WHILE the thread is running and relaunch and a flag will prevent it from starting a new instance of the same thread (unless the other one is done of course).</em></p> <p><em>Now my problem: My app's home screen is a list of buttons, when the user clicks one of these buttons another, more detailed list is loaded (this requires a READ ONLY call to the database). When I launch the app (firing the web service calling thread) and then click a button on the main screen right away, the table gets locked. (Not always, sometimes it takes 4 or 5 tries, sometimes more, sometimes less). But if I keep doing this it WILL eventually lock making it impossible to make any calls to my DB, hence no more UI (which depends on the DB).</em></p> <p><em>The DB call that populates the UI on the second screen is READ ONLY, can't I have as many of these as I need?? What causes the DB to lock?? What's the difference between a DB lock and File System error (12)??</em></p>

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