expresing grouping in W3c XQuery?

, ,
1

Is it possible to express functionality of group by statement known from Sql? If it is possible please provide some examples.

2

There’s no direct equivalent to group-by in the current XQuery draft, though there is still a possibility it will get in before version 1.0 is finalized.

Meanwhile you effectively have to hand-code it using the xf:distinct-nodes and xf:distinct-values functions.

Michael Kay

3

Can you post a simple example of XQuery code
that would utilize xf:distinct-values and function as a ‘GROUP BY’ statement?

4

The spec is still fluid in this area, and I haven’t checked exactly what’s implemented in QuiP or in Tamino 4.1, but the following gives the idea:

for $i in distinct-values(//employee/deparment/name)
return

{ for $e in //employee
where $e/department/name = $i
return $e
}


I hope this helps!

Michael Kay