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16.5.13. Linked Data Views and recursive FK relationships
Here is sample example of a script to include an additional table alias for a table:
alter quad storage virtrdf:DefaultQuadStorage
:
FROM isports_rdf.prs10_isports_rdf.VRef_Call as Ref_Call_tbl
FROM isports_rdf.prs10_isports_rdf.VRef_Call as Ref_Call_tbl_1
:
{
:
refcall:ref-call_iri (Ref_Call_tbl.Call_Num) a refcall:Ref-Call as
virtrdf:ref-call_pk ;
:
refcall:has_parent refcall:ref-call_iri (Ref_Call_tbl_1.Call_Num)
where ( ^{Ref_Call_tbl.}^.Parent = ^{Ref_Call_tbl_1.}^.Call_Num ) as
virtrdf:Ref-Call_has_parent .
This demonstrates the way to self-join the table VRef_Call with itself. Like in SQL, are needed two different aliases for one table if you want to join it with itself.