This document provides guidance on keeping a PHP application and its database in sync during development. It recommends: 1. Using multiple environments (dev, QA, staging) to test changes before releasing to production. 2. Tracking database changes through release scripts and deltas that are version controlled alongside code changes. 3. Communicating database changes between developers through emails or automatically applying deltas. 4. Encapsulating database changes, including stored procedures, in version controlled XML deltas that are referenced by all environments to stay in sync.

1. KEEPING YOUR DATABASE AND PHP IN SYNC
MAGGIE NELSON
MAY 22, 2008

2. dev prod

3. dev prod

4. dev qa prod

5. dev qa staging prod

6. dev1
(new stuff)
dev2 qa1 staging prod
(new stuff) (new stuff)
dev3 qa2
(maintenance) (maintenance)

7. new stuff
trunk
maintenance 1.0 2.0 3.0

8. PHP and DB are separate

9. = +
PHP
= +
PHP

10. releaseNumber.sql

11. release 2.0
+
PHP
cut 2.0 release at run release.2.0.sql
install 2.0 code
svn revision 207 in database

12. reverting release 2.0
+
PHP
revert to previous
???
version of code (prior to
in database
svn revision 207)

13. new stuff
r203 r207 r415
trunk
1-203 204-207 208-415
maintenance 1.0 2.0 3.0

14. releaseNumber.undo.sql

15. reverting release 2.0
+
PHP
revert to previous
run release.2.0.undo.sql
???
version of code (prior to
in database
in database
svn revision 207)

16. Frequent database changes during
release cycle

17. Frequent changes from dev -> QA
dev qa staging prod
run statements from
update QA with figure out last update
release.2.0.0.sql since
freshest PHP code ran from release.2.0.sql
last DB updates

18. releaseNumber.sql

19. releaseNumber.sql

20. Communication between developers

21. dev1
(new stuff)
dev2 qa1 staging prod
(new stuff) (new stuff)
dev3 qa2
(maintenance) (maintenance)

22. devs making DB changes
dev1 dev2
run statements from
update devX with figure out last update
release.2.0.0.sql since
freshest PHP code ran from release.2.0.sql
last DB updates

23. dev1 writes new code
database YES dev1 sends e-mail to dev2 with
dev1 commits code
changes? instructions for the DB change
NO
dev2 NO
dev2: svn up to get
checks dev2: svn up
new code
email?
YES
dev2 reads
instructions
dev2
dev2 has new YES follows NO dev2 environment is
instructions
code correctly? broken
EPIC FAIL

24. releaseNumber.sql

25. DB deltas

26. DB deltas as XML

27. dev1 writes new code
database YES encapsulate DB
changes? change in a delta
NO
dev1 commits code
dev2: svn up to get run script to check for new YES run script to parse and
new code new deltas deltas? apply new deltas
NO
dev2 has new
code

28. Stored procedures

29. Calling stored procedures from PHP

30. Oracle example - pkg header

31. Oracle example - pkg body

32. friend_pkg
db/Friend/pkg.sql
(header)
friend_pkg
db/Friend/pkg_body.sql
(body)
models models/FriendModel.php
views views/addFriend.phtml
controllers/
controllers
FriendController.php

33. Stored procedures in deltas

34. Reference, don’t copy

35. svn cat -r[some_revision] Friend/pkg.sql >> runThis.sql
svn cat -r[some_revision] Friend/pkg_body.sql >> runThis.sql
[some_revision] ??

36. encapsulate DB changes (DDL + DML) in a delta
(e.g. delta7.xml)
make stored procedure changes
reference stored procedure changes in the delta
make PHP changes
commit PHP changes, stored procedure
changes and the new delta7.xml

37. svn log -r PREV:HEAD delta7.sql
------------------------------------------------------------------------
r107 | maggie_n | 2008-02-25 15:13:50 -0500 (Mon, 25 Feb 2008) | 15 lines

38. svn log -r PREV:HEAD delta7.sql --xml
<?xml version=quot;1.0quot;?>
<log>
<logentry
revision=quot;107quot;>
<author>maggie_n</author>
<date>2008-02-25T20:13:50.097229Z</date>
<msg>My awesome delta number 7.</msg></logentry>
</log>
$deltaSvnRevision = $myXml->logentry[0][‘revision’];

39. Automagically...

45. Communication between development
branches

46. dev1
(new stuff)
dev2 qa1 staging prod
(new stuff) (new stuff)
dev3 qa2
(maintenance) (maintenance)

47. new stuff
trunk
maintenance 1.0 2.0 3.0
svn:external deltas

48. svn:externals
http://svn.example.com/svn/myapp/
trunk
branch/
new_stuff/
1.0/
2.0/
3.0/
deltas/

49. create new deltas directory parallel to trunk and
branches
in trunk or branch you’re working in:
svn propedit svn:externals .
edit file that opens, add:
deltas http://svn.example.com/myapp/deltas
save and exit
svn up
svn commit

50. new stuff
trunk
maintenance 1.0 2.0 3.0
svn:external deltas
deltas 1-...

51. central file to associate delta 2 branch/trunk
trunk: branches/1.0
- delta1 - delta1
- delta2
branches/2.0
branches/new_stuff - delta1
- delta3 - delta2
- delta4
branches/3.0
- delta1
- delta2
- delta3
- delta4

52. new stuff
trunk
maintenance 1.0 2.0 3.0

53. Summary
PHP + DB + XML + svn = awesome!

54. Questions?

55. Thanks!
more info:
maggienelson.com