| '''Summary'''
|Opens the database specified by <code>[[#Database Nodes|$db]]</code> and returns the node with the specified {{Mono|$id}} value.<br />Each database node has a persistent ''id'', which remains valid after update operations. If no updates are performed, the ''pre'' value can be requested, which provides access to database nodes in constant time.
|-
| '''Errors'''
|'''[[XQuery Errors#BaseX Errors|BXDB0009]]''' is raised if the specified id value does not exist in the database.
|}