Finding Compact Scheme Forests in Nested Normal Form Is NP-Hard
نویسندگان
چکیده
منابع مشابه
Finding Compact Scheme Forests
In traditional relational databases, the data is stored in \ at" tables. Query processing performance is dominated by the cost of joining such tables. By contrast, nested relational structures can avoid joins. If, however, such structures are decomposed into nested normal form (NNF) then the number of normal scheme trees in the resulting nested scheme forest may dominate query processing perfor...
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ژورنال
عنوان ژورنال: Information and Computation
سال: 1994
ISSN: 0890-5401
DOI: 10.1006/inco.1994.1022