Keyphrases
- database
- query language
- database queries
- databases
- indexing techniques
- answering queries
- semantic query
- access methods
- relational database systems
- query processing
- database systems
- semantic categories
- pre computed
- stored data
- relational databases
- query evaluation
- database schema
- null values
- complex queries
- vertical partitioning
- user queries
- information retrieval systems
- data sets
- domain ontology
- retrieval systems
- statistical databases
- web databases
- efficient processing
- semantic information
- language model
- response time
- data model
- natural language