Adding Valid Time - Part A
نویسندگان
چکیده
منابع مشابه
Adding Valid Time to XPath
In this paper we extend the XPath data model and query language to include valid time. XPath is a language for specifying locations within an XML document. We extend XPath’s data model by adding to each node a list of disjoint intervals or instants that represents the valid time. The valid time for a node is constrained to be a subset of the valid time for a node’s parent. We extend the XPath q...
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Temporal database management systems should offer user-friendly and powerful means of retrieval of data according to temporal criteria. Selection of tuples according to their valid times, which is the times when the information represented by the tuples is valid in the modeled reality [16], is termed valid-time selection. The attributes to be computed and returned from a query are specified in ...
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