Due to the flexible structures of SQL, no general approach works efficiently for all kinds of queries. Some special kinds of queries can be further optimized for better performa...
Systems designed for efficient retrieval of conventional data can be very inefficient at retrieving documents. Documents have more complex structure than conventional data, and th...
One of the most powerful features of SQL is the use of nested queries. Most research work on the optimization of nested queries focuses on aggregate subqueries. However, the solut...
Expressing complex OLAP queries using group-by, aggregation, and joins can be extremely difficult. As a result of this, many alternate ways of expressing such queries have been de...
Most declarative SQL-like query languagesfor object-oriented database systems (OOSQL) are orthogonal languages allowing for arbitrary nesting of expressions in the select-, from-,...
Hennie J. Steenhagen, Peter M. G. Apers, Henk M. B...