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






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






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






4. Another word for existence-independent is ____.






5. 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.






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






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






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






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






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






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






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






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






14. 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.






15. 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.






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






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






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






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






20. 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.






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






22. Improving ___ leads to more flexible queries.






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






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






25. A ______ attribute can have only one value.






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






27. 1NF - 2NF - and 3NF are _____.






28. 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.






29. 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 ____.






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






31. An ERM is not dependent on the ____________.






32. Data redundancy produces ____.






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






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






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






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






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






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






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






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






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






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






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






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






45. ________ cannot be further subdivided.






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






47. 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.






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






49. A ___________ must not contain a repeating group .






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