The text search engine allows queries to be formed from arbitrary Boolean expressions containing the keywords AND, OR, and NOT, and grouped with parentheses. For example:
- information retrieval
- finds documents containing 'information' or 'retrieval'
- information or retrieval
- same as above
- information and retrieval
- finds documents containing both 'information' and 'retrieval'
- information not retrieval
- finds documents containing 'information' but not 'retrieval'
- (information not retrieval) and WAIS
- finds documents containing 'WAIS', plus 'information' but not 'retrieval'
- web*
- finds documents containing words starting with 'web'