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 to obvious but it re-enforces your understanding as you take the test each time.
1. For most business transactional databases - we should normalize relations into ____.






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






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






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






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






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






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






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






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






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






11. Data redundancy produces ____.






12. ____ yields better performance.






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






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






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






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






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






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






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






20. 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.






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






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






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






24. 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.






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






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






27. 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.






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






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






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






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






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






33. 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.






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






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






36. A ___________ must not contain a repeating group .






37. An ERM is not dependent on the ____________.






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






39. 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.






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






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






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






43. A ______ attribute can have only one value.






44. Another word for existence-independent is ____.






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






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






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






48. Improving ___ leads to more flexible queries.






49. 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.






50. 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.