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






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






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






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






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






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






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






9. Improving ___ leads to more flexible queries.






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






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






12. A ______ attribute can have only one value.






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






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






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






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






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






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






19. ________ cannot be further subdivided.






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






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






22. 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.






23. 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 ____.






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






25. ____ yields better performance.






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






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






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






29. 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.






30. 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.






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






32. Data redundancy produces ____.






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






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






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






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






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






38. 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.






39. A ___________ must not contain a repeating group .






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






41. 1NF - 2NF - and 3NF are _____.






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






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






44. 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.






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






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






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






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






49. Another word for existence-independent is ____.






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