Query processing over incomplete autonomous databases: query rewriting using learned data dependencies
نویسندگان
چکیده
منابع مشابه
Query Processing over Incomplete Autonomous Databases
Incompleteness due to missing attribute values (aka “null values”) is very common in autonomous web databases, on which user accesses are usually supported through mediators. Traditional query processing techniques that focus on the strict soundness of answer tuples often ignore tuples with critical missing attributes, even if they wind up being relevant to a user query. Ideally we would like t...
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Incompleteness due to missing attribute values (aka “null values”) is very common in autonomous web databases, on which user accesses are usually supported through mediators. Traditional query processing techniques that focus on the strict soundness of answer tuples often ignore tuples with critical missing attributes, even if they wind up being relevant to the user query. Ideally, the mediator...
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Optimizing the database queries is one of hard research problems. Exhaustive search techniques like dynamic programming is suitable for queries with a few relations, but by increasing the number of relations in query, much use of memory and processing is needed, and the use of these methods is not suitable, so we have to use random and evolutionary methods. The use of evolutionary methods, beca...
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ژورنال
عنوان ژورنال: The VLDB Journal
سال: 2009
ISSN: 1066-8888,0949-877X
DOI: 10.1007/s00778-009-0155-0