never affect the original input file. You can, however, use the [[Commands|EXPORT]] command or the fn:put() function to create an updated XML file. Turning on the WRITEBACK property ([[Commands|SET Command]]) directly propagates changes of your database to the original input file. Make sure you back up your data in advance, as this approach modifies the underlying XML file.</p>
<p>As BaseX aims mainly for efficiency, the maintenance of indexes is left to the user.
This requires the user to call the [[Commands#Optimize|Optimize]]