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. Improving ___ leads to more flexible queries.






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






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






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






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






6. 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.






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






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






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






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






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






12. An ERM is not dependent on the ____________.






13. 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.






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






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






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






17. ____ yields better performance.






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






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






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






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






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






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






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






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






26. 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.






27. Another word for existence-independent is ____.






28. 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.






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






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






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






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






33. 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.






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






35. 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.






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






37. Data redundancy produces ____.






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






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






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






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






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






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






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






45. 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.






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






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






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






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






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