Keyphrases
- query optimization
- database systems
- cost model
- cardinality estimation
- query processing
- query execution
- multidatabase systems
- xml data
- query scheduling
- continuous queries
- semantic query optimization
- cost estimation
- query optimizer
- selectivity estimation
- efficient execution
- approximate query answering
- databases
- query execution plans
- bitmap indexes
- data placement
- query plan
- data mining
- index structure