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Nowadays, current trends of universal quantification-based queries are been oriented towards flexible ones (tolerant queries and-or those involving preferences). In this paper, we are interested in universal quantification-like queries dealing with both positive or negative preferences (requirements or prohibitions), considered separately or simultaneously. We have emphasised the improvement of the proposed operator, by designing new variants of the classical Hash-Division algorithm, presented in [1], for dealing with our context. The parallel implementation is also presented, and the issue of answers ranking is dealt with. Computational experiments are carried out in both sequential and parallel versions. They shows the relevance of our approach and demonstrate that the new operator outperforms the conventional one with respect to performance (the gain exceeds a ratio of 40).

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