Select the union or intersection of node sets.
With a SetExpr you can select the union or intersection of
node sets. A union set is constructed by using the operator | and
contains all nodes that are in any one of the node sets. An intersection is
constructed by using the operator intersect and contains only
those nodes that are in all nodes.
It corresponds to the expression UnionExpr defined in
XPath, Section 3.3,
Rule 18. However, X-Query adds the intersect operator
which is not present in XPath.
Select the union of all medication descendants and
diagnosis descendants of patients:
/patient//medication | /patient//diagnosis
Select the intersection of all patients born in 1950 and patients with medication in tablet form among all male patients:
/patient[born=1950] intersect /patient[//medication/type[@form='tablet']] intersect /patient[sex ~= 'male']
Certainly, you can write this query easier, for example:
/patient[born=1950 and .//medication/type[@form='tablet'] and sex ~= 'male']
Location
Path |
PrimaryExpr |
Predicate |
