Keyphrases
- query optimization
- database systems
- cost model
- query processing
- query execution
- cost estimation
- cardinality estimation
- xml data
- multidatabase systems
- data placement
- semantic query optimization
- query optimizer
- query scheduling
- efficient execution
- query execution plan
- complex queries
- efficient query processing
- query optimizers
- selectivity estimation
- approximate query answering
- data management