Characterizing Tractability of Simple Well-Designed Pattern Trees with Projection
نویسندگان
چکیده
منابع مشابه
Efficient Evaluation of Well-designed Pattern Trees (Extended Abstract)
Conjunctive queries (CQs) constitute the core of the query languages for relational databases and also the most intensively studied querying mechanism in the database theory community. But CQs suffer from a serious drawback when dealing with incomplete information: If it is not possible to match the complete query with the data, they return no answer at all. The semantic web therefore provides ...
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ژورنال
عنوان ژورنال: Theory of Computing Systems
سال: 2020
ISSN: 1432-4350,1433-0490
DOI: 10.1007/s00224-020-10002-z