Challenges 63. What decade is this quote from? 62. A surrogate key without an alterate key, can it be? 61. A Party for Vanishing Definitions 60. PDM = Implementation? 59. Making the Connections 58. Data Slang 57. Who is responsible for the data model actually being used? 56. SCD Type 3 for me? 55. How long will the modeling take? 54. Who owns the data model? 53. Data Modeling in the Cloud  52. Agile Enterprise Data Modeling,  an oxymoron? 51. Recycle, Reduce, Reuse 50. Where does XML fit? 49. Is Cost a Fact? 48. Swimming in Rough Water 47. Producing Adequate Definitions 46. Data becoming Metadata 45. My Hero Zero 44. As low as you can go 43. AAs vs. DAs 42. What's a good name for the high level model? 41. Business intelligence? 40. Is GUID good? 39. Canonical Data Model Defined 38. The Spam Model 37. Product Availability 36. Ontology and Taxonomy 35. Customer Id 34. Subtype key 33. Timeless Dimensional Model 32. Thinking Data 31. A Dimensional EDM 30. Recursive fact table? 29. Broken shells 28. Null AK? 27. Data Dictionary, are you out there? 26. Rules on rules 25. Super Star 24. Definition Differences 23. Creative hierarchy 22. Getting physical with subtypes 21. Role of the data architect 20. Decoding codes 19. Aggregation, summarization, and abstraction demystified 18. Dimensional logical? 17. Global Address 16. To surrogate key or not to surrogate key, that is the question 15. Medals for Model Layout 14. The Person Identifier 13. Enterprise Data Model ROI 12. Logical Data Modeling in practice 11. A Recursive Riddle 10. A Permission Puzzle 9. A tough rule 8. Define a "Thing" 7. We live in a world of classifications 6. Taming the wild west modeler 5. Technical questions asked during a job interview for a data-related position 4. Techniques in reviewing a data model 3. Convincing project teams of the need to normalize 2. Create a logical data model? 1. Having the same primary key in two or more logical entities

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