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






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






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






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






5. An ERM is not dependent on the ____________.






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






7. 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 ____.






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






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






10. 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.






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






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






13. ________ cannot be further subdivided.






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






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






16. A ___________ must not contain a repeating group .






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






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






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






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






21. Another word for existence-independent is ____.






22. 1NF - 2NF - and 3NF are _____.






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






24. 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.






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






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






27. 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 ____.






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






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 ___ identifier is composed of more than one attribute.






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






32. Data redundancy produces ____.






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






34. 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.






35. 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.






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






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






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






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






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






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. A ___ attribute is one that cannot be subdivided.






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






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






45. A ______ attribute can have only one value.






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






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






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






49. ____ yields better performance.






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