1. Why notORM? Michal paek, Skype;WebExpo 2010 , Prague

2. OMGWTF ORM ? 3. O bject- R elationalM apping ! 4. ORM,SRSLY ? 5. PHP/ORM guru ,anyone ?

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6. ORM maps relational databases to objects says Frantiek Trster 7. ORM maps relational databases to objects says Frantiek Trster maps objects to relational databases says Ji Knesl 8. ORM maps relational databases to objects says Frantiek Trster maps objects to relational databases says Ji Knesl is a technique for converting data between incompatible type systems in OOP languages says Wiki Pedia 9. ORM islike 10. TDD 11. Best thing since sliced bread . Or maybenot . 12. ORM is said to allow the database systems swap on the fly 13.

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14. , but have anyone seen it,ever ? 15. Most of the times you'll end up changing bunch of other things too,so it's not that easy as it might seem . 16. When your O/R mapper goesbananas 17. ORM expert

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18. Database system expert

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19. Using ORM and want torefactor relations ? 20. Do it, pretty please, but you have to refactorcodetoo 21. and you need to deploy all the changed stuffat once ! 22. And what about accessing one database with several technologies?

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23. Put your business logic into thedatabase ! 24. 25. 26. Issues solved ( allof them)

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27. Database code can be testedseparately from the rest of the code 28. Application code tests donot need a connection to the database 29. Forgetexplicit transactions( BEGIN &COMMIT )if you can has your codes wrapped infunctions 30. You'llget 31. Nice connection pooling

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32. Every query can be executedon different machine 33. Add proxies

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34. and get high performance clusters

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35. 36. Because we got notransactions 37. Teams of databasedevelopersandadmins 38. canmonitorfunctions and theirperformance 39. can redirect functions to beexecutedin differentdatabasewhen something goes horribly wrong 40. are generallyuseless while using ORM http://www.xkcd.com/303/ ORM, DUDE! 41. While withoutORM 42. everything's possible!

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43. WillYOUstop using ORM? 44. Problemssummarized :

getting external help

45. refactoring relations 46. multiple technologies 47. tricky testing 48. inefficient connection pooling 49. admins are hopeless, if any 50. performance monitoring and control 51.

Thanks for listening Michal paek Skype:spazef0rze ; Twitter: @ spazef0rze BTW, we're hiring: jobs.skype.com/cz