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






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






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






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






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






6. 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.






7. 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.






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






9. Another word for existence-independent is ____.






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






11. An ERM is not dependent on the ____________.






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






13. 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 ____.






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






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






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






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






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






19. 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.






20. 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.






21. 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 ____.






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






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






24. ____ yields better performance.






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






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






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






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






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






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






32. 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.






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






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






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






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






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






38. A ______ attribute can have only one value.






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






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






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






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






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






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






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






46. 1NF - 2NF - and 3NF are _____.






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






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






49. 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.






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