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






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






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






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






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






6. 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.






7. Another word for existence-independent is ____.






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






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






10. 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.






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






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






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






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






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






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






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






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






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






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






21. ________ cannot be further subdivided.






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






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






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






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






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






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






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






29. 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.






30. 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 ____.






31. 1NF - 2NF - and 3NF are _____.






32. An ERM is not dependent on the ____________.






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






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






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






36. A ___________ must not contain a repeating group .






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






38. 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.






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






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






41. 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.






42. 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.






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






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






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






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






47. A ______ attribute can have only one value.






48. Improving ___ leads to more flexible queries.






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






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