Accessing Databases by using a Filesystem

Transcript

1. Chris Brown Databases Accessing Filesystem by using a
2. Recap
3. Database Filesystem
4. Files & Folders
5. Excel
6. Progress
7. Reading from a Database
8. Reading from a Database ✓
9. Writing to a Database
10. Writing to a Database ✓
11. Querying the Database
12. Querying the Database ?
13. Problems
14. How can we query the database?
17. SQL
18. SQL
19. SQL Complicated
20. SQL Complicated Different Dialects
21. SQL Complicated Different Dialects Not-user Friendly
22. Relational Algebra
23. SQL + Pig Latin
24. SQueaL
25. Relational Algebra → SQL
26. users = Table :users grades = Table :grades predicate = users[:name].eq("Chris Brown") user_grades = join(users, grades, :id, :user_id) user_where = where(user_grades, predicate) user_window = limit(user_where, 1) Output select(user_window, users[:mark])
27. SELECT "users"."mark" FROM "users" INNER JOIN "grades" ON "users"."id" = "grades"."user_id" WHERE "users"."name" = 'Chris Brown' LIMIT 1
28. Easily Sequential-able
29. Demo
30. Next Steps
31. Start Writing Report
32. Finish next stage of programming
33. Questions? http://github.com/xoebus/fuseql http://github.com/xoebus/squeal http://github.com/xoebus/bacon