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






2. Improving ___ leads to more flexible queries.






3. ____ yields better performance.






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






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






6. Another word for existence-independent is ____.






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






8. 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.






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






10. 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 ____.






11. 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.






12. An ERM is not dependent on the ____________.






13. 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.






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






15. A ___________ must not contain a repeating group .






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






17. 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.






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






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






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






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






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






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






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






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






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






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






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






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






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






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






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






33. 1NF - 2NF - and 3NF are _____.






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






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






36. 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.






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






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






39. 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.






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






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






42. Data redundancy produces ____.






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






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






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






46. ________ cannot be further subdivided.






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






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






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






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