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






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






3. ____ yields better performance.






4. ________ cannot be further subdivided.






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






6. When a nonkey attribute is the determinate of a key attribute the table is in 3NF but not ____.






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






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






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






10. In order to meet performance requirements - you may have to denormalize portions of the ________.






11. 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.






12. 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.






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






14. 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.






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






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






17. Relationship strength depends on how the primary key of the related entity is formulated - while the relationship ____ depends on how the business rule is written.






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






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






20. Need not be stored physically in the data base.






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






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






23. A ___________ must not contain a repeating group .






24. A ___ identifier is composed of more than one attribute.






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






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






27. The conflicts between design efficiency - ____________ - and processing speed are often resolved through compromised that include denormalization.






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






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






30. An example of denormalization is using a ___ denormalized table to hold report data. This is required when creating a tabular report in which the columns represent data that is stored in the table as rows.






31. Data redundancy produces ____.






32. An ERM is not dependent on the ____________.






33. Most designers consider the BCNF as a special case of the ____.






34. Data redundancies occur from ____ of data on every row entry.






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






36. Another word for existence-independent is ____.






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






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






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






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






41. 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.






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






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






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






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






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






47. 1NF - 2NF - and 3NF are _____.






48. A ______ attribute can have only one value.






49. A _____ entity is composed of the primary keys of each of the entities to be connected.






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