Keyphrases
- query processing
- answering queries
- approximate answers
- correct answers
- user defined
- response time
- result set
- query language
- query evaluation
- aggregation queries
- aggregate queries
- skyline queries
- efficient processing
- query answering
- range queries
- web snippets
- natural language queries
- inverted index
- exact and approximate
- answering questions
- natural language questions
- web search engines
- tree patterns
- candidate set
- query answers
- databases
- database queries
- query logs
- relational databases
- database systems