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






2. 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.






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






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






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






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






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






8. 1NF - 2NF - and 3NF are _____.






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






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






11. 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.






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






13. Improving ___ leads to more flexible queries.






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






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






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






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






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






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






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






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






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






23. 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.






24. 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.






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






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






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






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






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






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






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






32. Data redundancy produces ____.






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






34. 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.






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






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






37. 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 ____.






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






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






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. 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.






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






43. ____ yields better performance.






44. A ______ attribute can have only one value.






45. ________ cannot be further subdivided.






46. Another word for existence-independent is ____.






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






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






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






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