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






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






3. ____ yields better performance.






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






5. Any attribute whose value determines other values within a row is called ____.






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






7. 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.






8. An ERM is not dependent on the ____________.






9. 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.






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






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






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






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






14. A ___________ must not contain a repeating group .






15. 1NF - 2NF - and 3NF are _____.






16. 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.






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






18. Improving ___ leads to more flexible queries.






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






20. 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.






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






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






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






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






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






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






27. Data redundancy produces ____.






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






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






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






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






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






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






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






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






36. 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.






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






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






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






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






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






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






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






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






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






46. ________ cannot be further subdivided.






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






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






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






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