1. The agile database migration framework for Java
@axelfontaine
Axel Fontaine axelfontaine.com
Software Development Expert business@axelfontaine.com

2. THE PLAN

3. WARNING!
Disruptive thinking
ahead!

4. The Problem

8. addAgeToAccount.sql

9. ?
? DB

10. DEV PROD
?
http://digitalcitizen.ca/2009/06/22/simpsons-profile-pics-for-facebook-and-other-applications/

11. VS
DML DDL

12. Problems for the DBA
• Little understanding of context
• Coordination with app deployer
• Monkey work
• Poor use of expertise
• Poor working hours

13. Problems for DEV
• Late review of changes
• Manual step with friction
• Less likely to change DB structure
• Code and DB diverge
• Incompatible with Continuous Deployment

14. Goals
Goals
• Cooperation between DEV and DBA
• Use full power of the DB
• (Almost) no lock-in
• Integrate in app so you can forget about it
• Descent working hours for everyone

15. flywaydb.org

16. 6
commands
clean info migrate validate init repair

19. Empty DB Version 1 Version 2

20. Flyway flyway = new Flyway();
flyway.setDataSource(myDataSource);
flyway.migrate();

21. Demo

22. DEV
Migrate PROD
on
Startup

23. Existing Production Database
align
DEV TEST PROD
V1__Dump.sql

24. Existing Production Database
align
DEV TEST PROD
V1__Dump.sql

25. Existing Production Database
align
DEV TEST PROD
migrate
V1__Dump.sql

26. Existing Production Database
align
DEV TEST PROD
migrate
V1__Dump.sql

27. Java Migrations
public class V1_2__Another_user implements JdbcMigration {
public void migrate(Connection conn) throws Exception {
PreparedStatement stmt = conn.prepareStatement(“…");
try {
stmt.execute();
} finally {
stmt.close();
}
}
}

28. Multiple Locations
http://www.flickr.com/photos/nrivera/3158808122/

30. Backwards Compatible
Migrations

31. DB Backup

32. DB Backup

33. DB

34. DB

35. DB

36. Example
Rename column
Surname -> Last_Name

37. Surname Last_Name
Surname
ALTER TABLE … RENAME COLUMN

38. Last_Name Last_Name
Surname Last_Name
ALTER TABLE … DROP TRIGGER …
ADD COLUMN Last_Name ALTER TABLE …
UPDATE … SET Last_Name = Surname DROP COLUMN Surname
CREATE TRIGGER …

39. Last_Name
Last_Name
DROP TRIGGER …
ALTER TABLE …
DROP COLUMN Surname

41. Roadmap
2.1 2.2 3.0

42. 1 day course
Effective Database
Migrations with Flyway
flywaydb.org/support/training.html

43. flywaydb.org

44. @axelfontaine
Axel Fontaine axelfontaine.com
Software Development Expert business@axelfontaine.com