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






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






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






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






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






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






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






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






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






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






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






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






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






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






16. A ___________ must not contain a repeating group .






17. Data redundancy produces ____.






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






19. 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.






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






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






22. A ______ attribute can have only one value.






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






24. ____ yields better performance.






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






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






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






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






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






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






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






32. ________ cannot be further subdivided.






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






34. 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.






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






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






37. 1NF - 2NF - and 3NF are _____.






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






39. 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.






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






41. 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.






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






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






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






45. An ERM is not dependent on the ____________.






46. 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 ____.






47. Another word for existence-independent is ____.






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






49. 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.






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