RE: Query on the XML graph

> I will tentatively suggest this:
> 
> I think there should be step/(s) to navigate id/idref. Reasons are:
> 
> 1. Now how do you traverse 2 idref edges in one path 
> expression; it is not very easy..
> 
> rough example: manager of managers:
> Id(Id(//Employee/@ReportsTo)/@ReportsTo)

You can write this as

//Employee/id(@ReportsTo)/id(@ReportsTo)
> 
> 2. We can think of extending recursive operators to idref 
> traversal, and
> say:
> 
> rough example: (This query can be written w/o recursion; but 
> we can think of transitive closure as something like this..??)
> //Employee/(@ReportsTo->Employee)*

This seems to be inventing recursive operators rather than extending
them. There is no such operator currently. If you want recursion, you
write a recursive function in XSLT or XQuery, which is just as easy to
do using id() as using a special operator.

Michael Kay