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






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






3. 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.






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






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






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






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






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






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






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






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






12. An ERM is not dependent on the ____________.






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






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. 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.






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






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






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






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






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






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






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






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






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






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






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






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






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






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






30. 1NF - 2NF - and 3NF are _____.






31. 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.






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






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






34. 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.






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






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






37. A ___________ must not contain a repeating group .






38. ____ yields better performance.






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






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






41. Improving ___ leads to more flexible queries.






42. A ______ attribute can have only one value.






43. 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 ____.






44. 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.






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






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






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






48. Another word for existence-independent is ____.






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






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