1. 7.PROGRAMMING METHODOLOGY
   1. 7.1Top-down Design
   2. 7.2An Interactive System
   3. 7.3A Simple Interactive Data Base System
      1. 7.3.1Design Definitions
      2. 7.3.2lookup a key in a database.
      3. 7.3.3Exercise
      4. 7.3.4lookup-all
      5. 7.3.5Exercise
      6. 7.3.6add_data Function
      7. 7.3.7remove_data Function
      8. 7.3.8Exercise
      9. 7.3.9remove_all_data Function
      10. 7.3.10Exercise
      11. 7.3.11Generalizing Software Constructions
      12. 7.3.12Specializing Operations to the people Database
      13. 7.3.13Reading and Writing Files
      14. 7.3.14Example
      15. 7.3.15Example
      16. 7.3.16lookup_file Function
      17. 7.3.17Example
      18. 7.3.18lookup_all_file Function
      19. 7.3.19Example
      20. 7.3.20add_data_file Function
      21. 7.3.21Example
      22. 7.3.22Specializing Operations to the people.db File
      23. 7.3.23people_file_looker Function
      24. 7.3.24Example
   4. 7.4Summary