Sqlite query returns mRowIdColumnIndex of -1

I need to check if there is already a value in one of my DB columns so I've written this code to do so:

             public Cursor getTitle(long rowId) throws SQLException {

 Cursor mCursor = db.query(DATABASE_TABLE, new String[] 
      {KEY_TOTAL_HOURS, KEY_TOTAL_MINUTES}, KEY_ROWID +"=" + rowId, null, null, null, null);{

     mCursor.moveToFirst();
     return mCursor;
 }
 }

But the cursor I'm getting back gives

android.database.CursorIndexOutOfBoundsException: Index 0 requested, with a size of 0
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What's wrong?

You should check the return value of moveToFirst to make sure there is a valid row returned: it will return false if there is not. It appears there is no row with the id you've specified.