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Improve AQL CONTAINS definition


It seems the semantics for CONTAINS in AQL is to select a child or descendant.

I think the spec needs to clarify this. The only place that the relationship involved in CONTAINS is mentioned seems to be here:

http://www.openehr.org/releases/QUERY/latest/docs/AQL/AQL.html Section 3.10.2:

"Since archetypes are in hierarchical structure, AQL has a containment constraint which specifies the hierarchical relationships between parent and child data items."

Only mentions parent-child, that can be interpreted as direct child. It would be good to add the semantics of CONTAINS explicitly as parent to child-or-descendant.

Also on section 3.10.2: "using keyword CONTAINS between two class expressions. Left class expression is the the parent object of the right class expression"

I think "parent" should be "ancestor".

"descendant" or "ancestor" are not mentioned in the current spec.



Pablo Pazos