Authors:
Ferdinando Di Martino
1
;
Salvatore Sessa
1
;
Giuseppe Polese
2
and
Mario Vacca
2
Affiliations:
1
Federico II University, Italy
;
2
Salerno University, Italy
Keyword(s):
Change propagation, Geographic databases, Instance update language, Mapreduce, Schema evolution, Spatial datasets.
Related
Ontology
Subjects/Areas/Topics:
Databases and Information Systems Integration
;
Enterprise Information Systems
;
Geographical Information Systems
;
Human-Computer Interaction
;
Object-Oriented Database Systems
Abstract:
Updating a schema is a very important activity which occurs naturally during the life cycle of database systems, due to different causes. A challenging problem arising when a schema evolves is the change propagation problem, i.e. the updating of the database ground instances to make them consistent with the evolved schema. Spatial datasets, a stored representation of geographical areas, are VLDBs and so the change propagation process, involving an enormous mass of data among geographical distributed nodes, is very expensive and call for efficient processing. Moreover, the problem of designing languages and tools for spatial data sets change propagation is relevant, for the shortage of tools for schema evolution, and, in particular, for the limitations of those for spatial data sets. In this paper, we take in account both efficiency and limitations and we propose an instance update language, based on the efficient and popular Map-Reduce Google programming paradigm, which allows to per
form in a parallel way a wide category of schema changes. A system embodying the language has been implementing.
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