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






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






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






4. 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.






5. Improving ___ leads to more flexible queries.






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






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






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






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






10. A table where all attributes are dependent on the primary key are independent of each other - and no row contains two or more multivalued facts about an entity - is said to be in ____.






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






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






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






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






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






16. 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.






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






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






19. 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.






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






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






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






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






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






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






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






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






28. Data redundancy produces ____.






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






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






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






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






33. Another word for existence-independent is ____.






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






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






37. A ______ attribute can have only one value.






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






39. 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.






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






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






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






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






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






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






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






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






48. 1NF - 2NF - and 3NF are _____.






49. A ___________ must not contain a repeating group .






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