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






2. 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.






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






4. Improving ___ leads to more flexible queries.






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






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






7. Data redundancy produces ____.






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






9. 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.






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






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






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






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






14. 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.






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






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






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






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






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






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






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






22. ________ cannot be further subdivided.






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






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






25. Another word for existence-independent is ____.






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






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






28. 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.






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






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






31. 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.






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






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






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






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






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






37. A ______ attribute can have only one value.






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






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






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






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






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






45. 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.






46. A ___________ must not contain a repeating group .






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






48. ____ yields better performance.






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






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