View examples of XQueries that involve hierarchies. The namespace keyword in the XQuery Prolog defines a namespace prefix. This prefix is used later in the query body. The context switching tokens, {) ...

Now we need to find the hierarchy of nodes with a higher level of 2 or more, as well as the zones of the highest-level nodes. For example, the first record has 3 levels of hierarchy, which are 5-11-15 ...

Moreover, given the virtually unlimited query space, it is impractical to enumerate and send all empty (or all non-empty) queries to the client to filter them. This paper introduces HQ-Filter, a ...