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    58     58   revert the database file to its original state.  The [COMMIT] occurs
    59     59   when the rollback journal is deleted.</p>
    60     60   
    61     61   <p>The WAL approach inverts this.  The original content is preserved
    62     62   in the database file and the changes are appended into a separate
    63     63   WAL file.  A [COMMIT] occurs when a special record indicating a commit
    64     64   is appended to the WAL.  Thus a COMMIT can happen without ever writing
    65         -to the original database, which allows reader to continue operating
           65  +to the original database, which allows readers to continue operating
    66     66   from the original unaltered database while changes are simultaneously being
    67     67   committed into the WAL.  Multiple transactions can be appended to the
    68     68   end of a single WAL file.</p>
    69     69   
    70     70   <tcl>hd_fragment ckpt checkpoint checkpointed checkpointing</tcl>
    71     71   <h3>Checkpointing</h3>
    72     72   
................................................................................
   230    230   <p>The journal_mode pragma returns a string which is the new journal mode.
   231    231   On success, the pragma will return the string "<tt>wal</tt>".  If 
   232    232   the conversion to WAL could not be completed (for example, if the VFS
   233    233   does not support the necessary shared-memory primitives) then the
   234    234   journaling mode will be unchanged and the string returned from the
   235    235   primitive will be the prior journaling mode (for example "<tt>delete</tt>").
   236    236   
   237         -<a name="how_to_checkpoint">
          237  +<a name="how_to_checkpoint"></a>
   238    238   <p>By default, SQLite will automatically checkpoint whenever a [COMMIT]
   239    239   occurs that causes the WAL file to be 1000 pages or more in size, or when the 
   240    240   last database connection on a database file closes.  The default 
   241    241   configuration is intended to work well for most applications.
   242    242   But programs that want more control can force a checkpoint
   243    243   using the [wal_checkpoint pragma] or by calling the
   244    244   [sqlite3_wal_checkpoint()] C interface.  The automatic checkpoint