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POAndroid & SQLite - Occasional error 'unable to close due to unfinalised statements'
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copied!<p>I seem to get the above error every so often in (an insert heavy) part of my code. I know normally this means there is an open Cursor within the connection but I have been through checking all my cursors are in try finally blocks and closed. Also in logcat the error reads 'sqlite3_close(...) failed: 5 which I think means the database is busy?</p> <p>The error can be 'ignored' if I add the following code to my finally block where the database connection is closed.</p> <pre><code> finally { writer.endTransaction(); boolean successAtClose = false; while(successAtClose == false) { try { writer.close(); successAtClose = true; } catch(Exception e) { e.printStackTrace(); } } dbConn.releaseLock(); } </code></pre> <p>When stepping through the code above the 'e.printStackTrace()' is hit once but on the second attempt the 'writer.close()' does not throw an error.</p> <p>Just to reiterate, this problem doesn't even happen every time the code block runs, the same data can be inserted say 5/6 times and only throw the error on one of these times. In addition the error does not reoccur straight away after happening once but continues to pop-up at random intervals.</p> <p>Does anyone know why this might occur? Or a better way to recover from this than the finally code above? (Since it will take me a long time to add this to all my database code.)</p> <p>ADDED:</p> <p>Database is opened with a custom <code>SQLiteOpenHelper</code> which is extended to use a reentrant lock to ensure only one thread accesses the database at any one time. So the start of the code is like:</p> <pre><code> MyDatabaseHelper dbConn = MyDatabaseHelper.getDatabaseAccess(c);//await availability/lock the database here SQLiteDatabase writer = dbConn.getWritableDatabase(); try { writer.beginTransaction(); //do inserts writer.setTransactionSuccessful(); </code></pre> <p>Get database access as follows:</p> <pre><code> public static MyDatabaseHelper getDatabaseAccess(Context c) { l.lock(); return new MyDatabaseHelper(c); } </code></pre> <p>As a further test I have further added a <code>Thread.sleep()</code> call to the finally code (in my case of 12 seconds), before the <code>close()</code> but after the <code>endTransaction()</code>, that seems to have stopped the error and confirm it is not a case of an open cursor, but I would rather not rely on a timer. If there is a better way, perhaps to pre-check whether the database is busy, please share.</p>

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