Test your basic knowledge |

Data Modeling

Subject : it-skills
Instructions:
  • Answer 50 questions in 15 minutes.
  • If you are not ready to take this test, you can study here.
  • Match each statement with the correct term.
  • Don't refresh. All questions and answers are randomly picked and ordered every time you load a test.

This is a study tool. The 3 wrong answers for each question are randomly chosen from answers to other questions. So, you might find at times the answers obvious, but you will see it re-enforces your understanding as you take the test each time.
1. Most designers consider the BCNF as a special case of the ____.






2. Another word for existence-independent is ____.






3. A table where all attributes are dependent on the primary key are independent of each other - and no row contains two or more multivalued facts about an entity - is said to be in ____.






4. From a structural point of view - ______ is better than 1NF






5. A ____ relationship exists when three entities are associated.






6. View the data as part of a table or collection of tables in which all key values must be identified.






7. The set of possible values for an attribute is a ____.






8. A table that has all key attributes defined - has no repeating groups - and all its attributes are dependent on the primary key - is said to be in ____.






9. Dependencies can be identified with the help of a dependency _____.






10. The ___ refers to a specific table row as an entity instance.






11. A table where every determinant is a candidate key is said to be in ____.






12. A talbe is in 4NF if it is 3NF and has no ________.






13. For most business transactional databases - we should normalize relations into ____.






14. A ___ relationship exists when two entities are associated.






15. In order to meet ___ requirements - you may have to denormalize some portion of the database.






16. According to naming conventions described in Chapter 2 - ___ would be the best name for a column representing the charges per hour in a table named JOB.






17. In a real-world environment - changing granularity requirements might dictate changes in primary key selection - and those changes might ultimately require the use of ____ keys.






18. Data redundancy produces ____.






19. The associative entity is also known as a ___ entity.






20. A ___ attribute is one that cannot be subdivided.






21. In the ERD - Cardinality is indicated using the ___ notation.






22. A ____ exists when there are functional dependencies such that Y is functionally dependent on X and Z is functionally dependent on Y - and X is the primary key.






23. BCNF can be violated only if the table contains more than one ___ key.






24. An attribute that is part of a key is known as a ____ attribute.






25. __________ is a process to help reduce the likelihood of data anomalies.






26. The word "entity" in the ER model corresponds to a _______.






27. A ___ entity has a primary key that is partially or totally derived from the parent entity in the relationship.






28. A ___ relationship exists when an association is maintained within a single entity.






29. If database tables are treated as though they were files in a file system - the ___ never has a chance to demonstrate its superior data-handling capabilities.






30. ____ yields better performance.






31. Improving ___ leads to more flexible queries.






32. A ______ attribute can have only one value.






33. Complex ____ requirements may dictate data transformations - and they may expand the number of entities and attributes withing the design.






34. 1NF - 2NF - and 3NF are _____.






35. If an employee within an EMPLOYEE entity has a relationship with itself - that relationship is known as a ____ relationship.






36. In a ___ diagram - the arrows above the attribute indicate all desirable dependencies.






37. Dependencies based on only a part of a composite primary key are called ___ dependencies.






38. Refers to the level of detail represented by the values stored in a table's row






39. If a table has multiple candidate keys and one of those candidate keys is a composite key - the table can have ___ based on this composite candidate key - even when the primary key chosen is a single attribute.






40. A table that is in 2NF and contains no transitive dependencies is said to be in ___.






41. A table is in BCNF if every determinant in the table is a ____________.






42. The existence of a(n) ___ relationship indicated that the minimum cardinality is at least 1 for the mandatory entity.






43. THE MOST LIKELY DATA TYPE FOR A SURROGATE KEY IS ____.






44. ______________database tables often lead to various data redundancy disasters in production databases.






45. The Crow's foot symbol with two parallel lines indicates ___ cardinality.






46. The following step occurs first in the process of building an ERD: create a __________ of the organization's description of operations.






47. Depicts all dependencies found within a given table structure is known as a ______.






48. An ERM is not dependent on the ____________.






49. A ___ derives its name from the fact that a group of multiple entries of the same type can exist for any single key attribute occurrence.






50. A ___________ must not contain a repeating group .