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






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






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






4. 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.






5. Another word for existence-independent is ____.






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






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






8. 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.






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






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






11. ____ yields better performance.






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






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






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






15. A ___________ must not contain a repeating group .






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






17. 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 ____.






18. 1NF - 2NF - and 3NF are _____.






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






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






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






22. Data redundancy produces ____.






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






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






25. An ERM is not dependent on the ____________.






26. ________ cannot be further subdivided.






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






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






29. Improving ___ leads to more flexible queries.






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






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






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






33. 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.






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






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






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






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






38. 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.






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






40. 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.






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






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






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






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






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






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






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






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






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






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