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






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






3. ____ yields better performance.






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






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






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






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






8. 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.






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






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






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






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






13. 1NF - 2NF - and 3NF are _____.






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






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






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






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






18. 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.






19. 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.






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






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






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






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






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






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






26. 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.






27. Improving ___ leads to more flexible queries.






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






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






30. A ______ attribute can have only one value.






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






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






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






34. ________ cannot be further subdivided.






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






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






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






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






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






40. 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.






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






42. Another word for existence-independent is ____.






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






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






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






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






47. 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.






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






49. Data redundancy produces ____.






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