Figure 8(b) shows
an example of intervals satisfying the related constraint.
Temporal Semistructured Data Models and Data Warehouses 2
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of Idea Group Inc. is prohibited.
Future.Trends
In the semistructured data warehouse context, the following issues are very relevant
and interesting:
??? Querying.of.semistructured.temporal.data.warehouse: Starting from a graphbased
representation of data stored in a data warehouse, it could be useful to
study a temporal semistructured query language which allows one to impose
temporal clauses, and retrieve information without knowing in advance the
structure of data. In the semistructured data context, query languages use path
Figure 7. A basic constraint
Figure 8. The constraint on the relation between a product and its categories
< NodeNameh , [ ths, the ] >
< EdgeNamej, [ tjs , tje ] >
ths the
tjs tje
tks tke
t
< NodeNamek, [tks , tke] >
he t je t
hs t js t
?‰¤
??§ ?‰?
(a) (b)
< NodeNameh , [ ths, the ] >
< Product, [tks , tke] >
< ProdListi , [ tis , tie ] >
t s t e
t2s
t s
t e
t e
tks tke
t
n 1,..., i
] ie t , is [t
) ie max(t ke t
) is min(t ks t
=
??… =
??§ =
??§ =
??‰
(a) (b)
2 4 Combi & Oliboni
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Idea Group Inc.
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