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Horizontal Fragmentation of Multimedia Databases to Optimize Content-based Queries: A Review

Horizontal fragmentation is a database technique widely used to optimize queries. This paper aims to provide a review of the literature about query optimization methods applied to multimedia databases, to determine if the methods use horizontal fragmentation to improve the performance of the database, are easy to implement, are complete (i.e., the paper includes all the necessary information to implement the method), takes into account content-based retrieval and if they provide a cost model for the evaluation of their results. To meet this objective, we analyze and classify 35 papers concerning fragmentation techniques and/or content-based image retrieval. Finally, we select the best method of our comparative analysis and present an architecture of a web application for a system that uses horizontal fragmentation to optimize content-based queries.