1. How we are going to decide which schema we are going to implement in the data warehouse?


2. What is the difference between logical data model and physical data model in Erwin?


3. Match the following in the context of data flow diagram : i. Circle a. Source of data ii. Square b. File or data base iii. Arrow c. Conversion process iv. Parallel line d. Data flow 1. L-a, ll-b,lll-c, lv-d 2. L-c, ll-a, lll-d, lv-b 3. L-c,ll-d, lll-a, lv-b 4. L-b, ll-a, lll-d, iv-c


4. Manages's salary details are hidden from employees This is 1. Conceptual level of data hiding 2. Physical level of data hiding 3. External level of data hiding 4. Either 1 or 2


5. Data Modeling software tools


6. In which normal form is the dimension table and fact table in the schema?


7. Conceptual Models


8. Why are recursive relationships are bad? How do you resolve them?


9. What is the difference between star flake and snow flake schema?


10. When should you consider denormalization?

11. Describe the third normal form?


12. What is second normal form ?


13. What is First Normal Form ?


14. Generally speaking,for a weak entity set to be meaningful it must be part of a 1. One-to-one relationship 2. One-to-many relationship 3. Many-to-many relationship 4. Depends on a particular situation

15. Data modelling is the process of constructing 1. An orderly arrangement of data elements 2. A graphic representation of data contained in an information system 3. Physical elements of the information system 4. A verbal description of the data need


16. What is ERD?


17. What is the difference between hashed file stage and sequential file stage in relates to datastage Server?


18. Is this statement TRUE or FALSE – all databases must be in third normal form?


19. What is data sparsity and how it effect on aggregation?


20. What is an artificial (derived) primary key? When should it be used?