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. 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.






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






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






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






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






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






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






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






9. ________ cannot be further subdivided.






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






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






12. Data redundancy produces ____.






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






14. 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 ____.






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






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






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






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






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






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






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






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






24. 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 ____.






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






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






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






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






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






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






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






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






33. 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.






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






35. An ERM is not dependent on the ____________.






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






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






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






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






40. Another word for existence-independent is ____.






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






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






43. 1NF - 2NF - and 3NF are _____.






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






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






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






47. ____ yields better performance.






48. 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.






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






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