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. ________ cannot be further subdivided.






2. ____ yields better performance.






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






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






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






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






7. 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 ____.






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. 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.






10. 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.






11. Another word for existence-independent is ____.






12. 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.






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






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






15. 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.






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






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






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






19. 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.






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






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






22. An ERM is not dependent on the ____________.






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






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






25. 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.






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






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






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






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






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






31. A ______ attribute can have only one value.






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






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






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






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






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






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






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






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






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






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






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






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






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






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






46. Data redundancy produces ____.






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






48. Improving ___ leads to more flexible queries.






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






50. A ___________ must not contain a repeating group .