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






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






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






4. 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 ____.






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






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






7. 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.






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






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






10. Improving ___ leads to more flexible queries.






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






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






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






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






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






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






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






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






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






20. ____ yields better performance.






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






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






23. 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.






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






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






26. A ___________ must not contain a repeating group .






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






28. 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.






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






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






31. Another word for existence-independent is ____.






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






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






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






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. 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.






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






38. ________ cannot be further subdivided.






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






40. Data redundancy produces ____.






41. 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.






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






43. 1NF - 2NF - and 3NF are _____.






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






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






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






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






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






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






50. An ERM is not dependent on the ____________.