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 ___ relationship exists when two entities are associated.






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






3. 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.






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






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






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






7. ____ yields better performance.






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






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






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






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






12. ________ cannot be further subdivided.






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






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






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






16. A ___________ must not contain a repeating group .






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






18. 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.






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






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






21. 1NF - 2NF - and 3NF are _____.






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






23. 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.






24. An ERM is not dependent on the ____________.






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






26. A ______ attribute can have only one value.






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






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






29. 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.






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






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






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






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






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






35. 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.






36. Data redundancy produces ____.






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






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






39. 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.






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






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






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






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






44. 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 ____.






45. 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.






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






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






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






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






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