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






3. 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.






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






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






6. ____ yields better performance.






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






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






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






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






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






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






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






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






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






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






17. 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.






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






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






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






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






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






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






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






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






26. An ERM is not dependent on the ____________.






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






28. A ___ entity has a primary key that is partially or totally derived from the parent entity in the relationship.






29. 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 ____.






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






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






32. 1NF - 2NF - and 3NF are _____.






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






34. 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.






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






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






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






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






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






40. 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.






41. 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 ____.






42. 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.






43. ________ cannot be further subdivided.






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






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






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






47. Improving ___ leads to more flexible queries.






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






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






50. 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.