Semantic Optimization of Conjunctive Queries
نویسندگان
چکیده
منابع مشابه
Semantic Optimization of Preference Queries
Preference queries are relational algebra or SQL queries that contain occurrences of the winnow operator (find the most preferred tuples in a given relation). We present here a number of semantic optimization techniques applicable to preference queries. The techniques make it possible to remove redundant occurrences of the winnow operator and to apply a more efficient algorithm for the computat...
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ژورنال
عنوان ژورنال: Journal of the ACM
سال: 2020
ISSN: 0004-5411,1557-735X
DOI: 10.1145/3424908