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)

     

     LQL for dbHotels Repository
     ALIAS	LQL Tree
     AUX-1
     AUX-4
     AUX-7
     AUX-10
     AUX-13

     LQL for XMLHotels Repository
     ALIAS	LQL Tree
     AUX-2
     AUX-5
     AUX-8
     AUX-11
     AUX-14

     LQL for WebSearchHotels Repository
     ALIAS	LQL Tree
     AUX-3
     AUX-6
     AUX-9
     AUX-12
     AUX-15

   • 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