3652 search results - page 206 / 731 » A study of query length |
LPAR
2007
Springer
14 years 2 months ago
2007
Springer
We study the data complexity of instance checking and conjunctive query answering in the EL family of description logics, with a particular emphasis on the boundary of tractability...
VLDB
1989
ACM
14 years 8 days ago
1989
ACM
: We describe the architecture of a relational databasesystem that is extensible by user-defined data types and operations, including relation operations. The central concept is to...
PVLDB
2008
13 years 7 months ago
2008
We study the problem of extracting flattened tuple data from streaming, hierarchical XML data. Tuple-extraction queries are essentially XML pattern queries with multiple extractio...
SIGMOD
2008
ACM
14 years 8 months ago
2008
ACM
Supporting ranking queries in database systems has been a popular research topic recently. However, there is a lack of study on supporting ranking queries in data warehouses where...
VLDB
2007
ACM
14 years 2 months ago
2007
ACM
A top-k query retrieves the k highest scoring tuples from a data set with respect to a scoring function defined on the attributes of a tuple. The efficient evaluation of top-k q...