Simple Demo: OBSERVER execution

1. Query Edition

   Retrieve the name, location and room rate for hotels with a room rate equals to $200

   [Name Location Price] of (AND hotel (FILLS Price 200))

2. DL query ==> Mappings
   • DL query ==> Multi-repository mappings
     
   • Multi-repository mappings ==> several mono-repository mappings
3. Access to data repositories
   • Mono-repository mappings ==> queries in Local Query Language (LQL)
   • Execution of LQL queries
     • Access data using wrappers
     • Applying transformer functions
   • Obtaining final answer using an auxiliar database
4. Presentation of answer to the user