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






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






3. 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.






4. ____ yields better performance.






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






6. A ___________ must not contain a repeating group .






7. A ______ attribute can have only one value.






8. 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 ____.






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






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






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






12. ________ cannot be further subdivided.






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






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






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






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






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






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






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






20. An ERM is not dependent on the ____________.






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






22. Another word for existence-independent is ____.






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






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






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






26. 1NF - 2NF - and 3NF are _____.






27. 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.






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






29. 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.






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






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






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






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






34. 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.






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






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






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






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






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






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






42. 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.






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






44. Data redundancy produces ____.






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






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






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






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






49. 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 ____.






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