Hi Alexander,
> Do you think this is a reliable perfomant solution to copy big files (can > not specifiy how big am, but could be > estimated more than 500MB ) - possible limitations in xquery ? > I would say so. Some bulk operations are only available via commands, but a lot of functionality for commands and XQuery is based on the same code. To reduce memory consumption, you can enable the ADDCACHE option [1], but it will slow down the execution a bit. As databases are lightweight objects in BaseX, you can also write all your files to a dedicated backup database. Best, Christian [1] https://docs.basex.org/main/Database_Functions#db:add
