Motivation
Database-style queries are effective
- Find red cars, 1993 or newer, < $5,000
- Select * From Car Where Color=“red” And Year >= 1993 And Price < 5000
Web is not a database
- Uses keyword search
- Retrieves documents, not records
- Assuming we have a range operator:
- “red” and (1993 to 1998) and (1 to 5000)