Class fragmentation is an important task in the design of Distributed OODBs and there are many algorithms handling it. Almost none of them deals however wiLh the class fragmentation order details. We claim that class fragmentation order can induce severe performance penalties if not considered in the fragmentation phase. We propose here two variants of an algorithm for finding the optimal class fragmentation order in a DOODB. In both variants we capture all class relations (inheritance, aggregation) and we determine a class fragmentation order where precedence conflicts induced by relation cycles are eliminated in such way that the strongest links be maintained.
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