1. State-based or migration- based database development? A review of the pros and cons

3. SQL Relay Birmingham 29 th October 2014 @_AlexYates_ workingwithdevs.com uk.linkedin.com/in/alexanderyates alex.yates@red-gate.com

4. SQL Relay Newcastle 27 th October 2014 @_AlexYates_ workingwithdevs.com uk.linkedin.com/in/alexanderyates alex.yates@red-gate.com

5. SQL Relay Birmingham 29 th October 2014 @_AlexYates_ workingwithdevs.com uk.linkedin.com/in/alexanderyates alex.yates@red-gate.com

7. Reliability  Safe deployments  Fire prevention over firefighting Visibility  Visualise pipeline  Better coordination DevOps  DBA + devs work together  Automation  Agility 12 3 Goals for project

11. V1V2

12. Migrations based solutions V1V2

13. State based solutions V1V2

15. “There's nothing more reliable than keeping track of exactly the scripts you intend to run, and running them, without trying to compare state and guess.” Paul Stovell, built Octopus Deploy

16. “There's nothing more reliable than keeping track of exactly the scripts you intend to run, and running them, without trying to compare state and guess.” Paul Stovell, built Octopus Deploy “As soon as you have multiple changes on a single aspect of an object, ordering and the ability to detect which change needs to be made gets very complicated.” Gert Drapers, built DataDude

17. Demo: the happy path! SOURCE CONTROL CONTINUOUS INTEGRATION AUTOMATED DEPLOYMENT

18. 11 2 Table rename  Table ‘foo’ is to be renamed ‘bar’ Edit stored procedure  Myproc to select col2 from table ‘foo’ (currently it selects only col1) Task

20. 0124_edit_sproc.sql ALTER PROCEDURE myproc AS BEGIN SELECT col1, col2 FROM table_foo END

21. 0124_edit_sproc.sql0125_table_rename.sql EXEC sp_rename 'table_foo', 'table_bar‘ ALTER PROCEDURE myproc AS BEGIN SELECT col1 FROM table_bar END ALTER PROCEDURE myproc AS BEGIN SELECT col1, col2 FROM table_foo END

22. 0124_edit_sproc.sql0125_table_rename.sql EXEC sp_rename 'table_foo', 'table_bar‘ ALTER PROCEDURE myproc AS BEGIN SELECT col1 FROM table_bar END ALTER PROCEDURE myproc AS BEGIN SELECT col1, col2 FROM table_foo END !

23. Conflicts easily missed  Changes overwritten Order matters  Last script wins To review changes  Much reading, but very important to get code right The problem with migrations

24. V123 myproc.sql CREATE PROCEDURE myproc AS SELECT col1 FROM table_foo !

25. V123 myproc.sql CREATE PROCEDURE myproc AS SELECT col1 FROM table_foo V124 myproc.sql CREATE PROCEDURE myproc AS SELECT col1, col2 FROM table_foo

26. V123 myproc.sql CREATE PROCEDURE myproc AS SELECT col1 FROM table_foo V124 myproc.sql CREATE PROCEDURE myproc AS SELECT col1, col2 FROM table_foo V125 myproc.sql CREATE PROCEDURE myproc AS SELECT col1 FROM table_bar

27. V123 myproc.sql CREATE PROCEDURE myproc AS SELECT col1 FROM table_foo V124 myproc.sql CREATE PROCEDURE myproc AS SELECT col1, col2 FROM table_foo V125 myproc.sql CREATE PROCEDURE myproc AS SELECT col1 FROM table_bar !

29. REVISION 123REVISION 124 table_foo.sql CREATE TABLE table_foo (col1 NVARCHAR(max), col2 NVARCHAR(max)) myproc.sql CREATE PROCEDURE myproc AS SELECT col1 FROM table_foo table_bar.sql CREATE TABLE table_bar (col1 NVARCHAR(max), col2 NVARCHAR(max)) myproc.sql CREATE PROCEDURE myproc AS SELECT col1, col2 FROM table_bar

30. Diff script: DROP TABLE table_foo CREATE TABLE table_bar (col1 NVARCHAR(max), col2 NVARCHAR(max)) ALTER PROCEDURE myproc AS SELECT col1, col2 FROM table_bar The problem with state

31. Diff script DROP TABLE table_foo CREATE TABLE table_bar (col1 NVARCHAR(max), col2 NVARCHAR(max)) ALTER PROCEDURE myproc AS SELECT col1, col2 FROM table_bar ! The problem with state

32. Script DROP TABLE table_foo CREATE TABLE table_bar (col1 NVARCHAR(max), col2 NVARCHAR(max)) ALTER PROCEDURE myproc AS SELECT col1, col2 FROM table_bar Need to understand your tool  It should be obvious to you that your tool won’t work What is the Plan B / override?  Because one day you’ll need it Test for data loss  Automatically (naturally) The problem with state

33. One more thing…

35. State  Easier (less control)  Better for sprocs/functions  Better for large/distributed teams  Better for frequent changes  Better for dependency nightmares  Drift: rolled back Migrations  More control (harder/needs discipline)  Better for data migrations  Better for small teams  Better for infrequent changes  Better for simple data stores  Drift: ignored So what is better?

36. State (+migrations)  SSDT pre/post deploy scripts  Redgate migrations Migrations (+state)  ReadyRoll ‘deploy changes’ Best of both worlds?

38. Reliability  Safe deployments  Fire prevention over firefighting 1 Goals for project

40. Reliability  Safe deployments  Fire prevention over firefighting Visibility  Visualise pipeline  Better coordination 12 Goals for project

41. Reliability  Safe deployments  Fire prevention over firefighting Visibility  Visualise pipeline  Better coordination DevOps  DBA + devs work together  Automation  Agility 12 3 Goals for project

43. @_AlexYates_ workingwithdevs.com/ delivering-databases-migrations-vs-state uk.linkedin.com/in/alexanderyates alex.yates@red-gate.com

44. Image sources AuthorSourceInformation ChiltepinsterWikimedia CommonsMocking Bird Argument.jpg – Wikimedia CommonsMocking Bird Argument.jpg – Wikimedia Commons. This file is licensed under the Creative Commons Attribution-Share Alike 3.0 Unported license. Source on Wikimedia Commons: “Own work”Creative CommonsAttribution-Share Alike 3.0 Unported TableatnyWikimedia CommonsAthlete at Starting block.jpg – Wikimedia CommonsAthlete at Starting block.jpg – Wikimedia Commons. This file is licensed under the Creative Commons Attribution 2.0 Generic license. Source on Wikimedia Commons: “BXP135671”Creative Commons Attribution 2.0 GenericBXP135671 Henry MühlpfordtFlickrCERN Atlas Control Room 2010-07-01 – FlickrCERN Atlas Control Room 2010-07-01 – Flickr. This file is licensed under the Creative Commons Attribution-ShareAlike 2.0 Generic license.Creative Commons Attribution-ShareAlike 2.0 Generic license Department for Business, Innovation and Skills FlickrToyota’s new Auris – FlickrToyota’s new Auris – Flickr. This file is licensed under the Creative Commons Attribution-NoDerivs 2.0 Generic license.Creative Commons Attribution-NoDerivs 2.0 Generic license Stephen WolfeFlickrViolinists – FlickrViolinists – Flickr. This file is licensed under the Creative Commons Attribution 2.0 Generic license.Creative Commons Attribution 2.0 Generic license Akira HsuFlickrThe Micro Four Thirds Logo by Empire Elite Stormtroopers - for the great “Micro Four Thirds Day” – FlickrThe Micro Four Thirds Logo by Empire Elite Stormtroopers - for the great “Micro Four Thirds Day” – Flickr. This file is licensed under the Creative Commons Attribution 2.0 Generic license.Creative Commons Attribution 2.0 Generic license Nils RinaldiFlickrHippo fight 2/3 – FlickrHippo fight 2/3 – Flickr. This file is licensed under the Creative Commons Attribution 2.0 Generic license.Creative Commons Attribution 2.0 Generic license My own collectionAll pictures are either of me, taken by friends/colleagues, or taken by me All pictures on about me slide, including kitten, and team at Farm Credit Services of America (FCSA). FCSA have allowed me/Redgate to reference the visit in presentations/marketing material etc. Memegenerator.net I don’t always edit database. Content designed to be shared and delivered with credit to memegenerator.net. Ctrl.Alt.Designctrla.ltSocial Media share icons