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. 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.






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






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






4. An ERM is not dependent on the ____________.






5. ____ yields better performance.






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






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






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






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






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






11. Another word for existence-independent is ____.






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






13. 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.






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






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






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






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






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






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






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






21. 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.






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






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






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






25. 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 ____.






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






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






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






29. A ______ attribute can have only one value.






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






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






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






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






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






35. 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 ____.






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






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






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






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






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






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






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






44. 1NF - 2NF - and 3NF are _____.






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






46. ________ cannot be further subdivided.






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






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






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






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