+ <para>
+ The multi filter consists of zero or more
+ <literal><target></literal> elements.
+ If a target matches a given target specified as CDATA in the
+ target element, the multi filter will route traffic to the route
+ given by the route attribute.
+ </para>
+ <para>
+ A target element is not required for multi-plexing to work.
+ It merely serves as a way to route differently.
+ </para>
+ <para>
+ If an empty
+ <literal><hideunavailable></literal>
+ element is placed inside the
+ <literal>multi</literal>
+ filter, then unavailable databases are not reported to the client,
+ but simply ignored (unless every one of the databases is
+ unavailable).
+ </para>