A comparison of two approaches to utilizing XML in parametric databases for temporal data

Modeling temporal dimensions of semistructured data

“…In Noh and Gadia (2006), the authors face a different issue, namely that of managing parametric temporal data through an XML encoding. Parametric temporal data are mainly temporal relations with attribute timestamping.…”

“…Finally, in Wang and Zaniolo (2004), the XML-based bitemporal data model XBiT is proposed: the authors show that validtime, transaction-time, and bitemporal databases can be naturally viewed in XML using temporally-grouped data models. Similarly to the approach proposed in Noh and Gadia (2006), here the focus in on the representation of temporally-grouped data: in these models tuples are composed by non-atomic multivalued timestamped attributes but all the attributes of a tuple have the same overall timespan. Then, authors show that complex historical queries, that would be very difficult to express in SQL on relational tables, may be easily expressed in standard XQuery on such XML-based representations.…”

An XML-based implementation of the parametric model for ad-hoc query of temporal and spatiotemporal data

“…In order to answer the question, we conducted the comparisons between the XML-based parametric temporal database system and native XML database systems. Our experiments [41] showed that the XML-based parametric temporal database system is more efficient and easy for processing and expressing temporal queries.…”

“…An instant t can be identified with the interval [t, £]; thus it can be regarded as a temporal element. Examples of temporal elements are [11,60] and [0,20] U [41,51]. The set of all temporal elements is closed under union, intersection, and complementation.…”

“…The concept of relations, tuples, attributes, and temporal elements can be mapped to XML elements so that the features of the data model can be simply transformed into XML without convoluting any properties. XML can even add additional information derived from the data model to achieve fast information retrieval of a query execution engine [44,41]. the attribute element <a n="Name"> can be expressed as <a> without using XML attributes because the attribute information can be stored in a system catalog.…”