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






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






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






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






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






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






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






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






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






11. Improving ___ leads to more flexible queries.






12. 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.






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






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






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






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






17. A ___________ must not contain a repeating group .






18. 1NF - 2NF - and 3NF are _____.






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






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






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






22. Another word for existence-independent is ____.






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






24. Data redundancy produces ____.






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






26. Normalization represents a micro view of the ___ within the ERD.






27. _______ databases reflect the ever-growing demand for greater scope and depth in the data on which decision support systems increasingly rely.






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






29. 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.






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






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






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






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






34. An ERM is not dependent on the ____________.






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






36. If you have three different transitive dependencies - ___ different determinants exist.






37. 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.






38. 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.






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






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






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






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






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






44. The price paid for increased performance through denormalization is a larger amount of ____.






45. From a system functionality point of view - ___ attribute values can be calculated when they are needed to write reports or invoices.






46. ________ cannot be further subdivided.






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






48. A ______ attribute can have only one value.






49. 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.






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