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copied!<ol> <li><p>What value is <code>sqlite3_step</code> returning? Put in a <code>NSLog</code> statement right before your <code>sqlite3_step</code> (and display the <code>numberOfRetries</code>). You later imply that it's hanging at the <code>sqlite3_step</code> function call, which seems unlikely.</p></li> <li><p>More likely, this routine is repeatedly calling <code>sqlite3_step</code> (e.g. if the database is busy and <code>[parentDB busyRetryTimeout]</code> is 0, this function would never end (or at least until the database contention was resolved). That's the only obvious problem that's leaping out at me, but it requires a confluence of multiple factors.</p></li> <li><p>Why is your database busy? Trying to use it in a background queue? Personally, for my apps that require background database operation, I create a separate <a href="https://developer.apple.com/library/mac/#documentation/General/Conceptual/ConcurrencyProgrammingGuide/OperationQueues/OperationQueues.html#//apple_ref/doc/uid/TP40008091-CH102-SW1" rel="nofollow">serial queue</a> in <a href="https://developer.apple.com/library/mac/#documentation/Performance/Reference/GCD_libdispatch_Ref/Reference/reference.html" rel="nofollow">GCD</a> queue for my database operations which, because it's serial, ensures that there is no database contention. Incidentally, if you ever want to get out of the weeds of SQLite programming, <a href="https://github.com/ccgus/fmdb" rel="nofollow">FMDB</a> is a wonderful wrapper, and it has a <code>FMDatabaseQueue</code> which takes care of all of this for you. If my conjecture of point 2 is right, you need to fix that first, but in general, FMDB simplifies background operations on databases.</p></li> </ol>

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