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






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






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






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






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






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






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. A ______ attribute can have only one value.






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






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






11. ________ cannot be further subdivided.






12. An ERM is not dependent on the ____________.






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






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






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






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






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. 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.






20. Another word for existence-independent is ____.






21. Improving ___ leads to more flexible queries.






22. ____ yields better performance.






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






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






25. 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 ____.






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






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






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






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






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






31. 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 ____.






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






33. 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.






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






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






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






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






38. 1NF - 2NF - and 3NF are _____.






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






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






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






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






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






45. 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.






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






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






48. Data redundancy produces ____.






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






50. 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.