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






2. ____ yields better performance.






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






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






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






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






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






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






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






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






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






12. 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.






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






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






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






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






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






18. Data redundancy produces ____.






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






20. An ERM is not dependent on the ____________.






21. 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.






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






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






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






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






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






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






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






29. 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.






30. 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.






31. ________ cannot be further subdivided.






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






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






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






35. 1NF - 2NF - and 3NF are _____.






36. Another word for existence-independent is ____.






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






38. A ___________ must not contain a repeating group .






39. 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.






40. A ______ attribute can have only one value.






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






42. 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.






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






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






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






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






47. Improving ___ leads to more flexible queries.






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






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






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