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






2. 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.






3. ____ yields better performance.






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






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






6. ________ cannot be further subdivided.






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






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






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






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






11. 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 ____.






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






13. 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.






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






15. Another word for existence-independent is ____.






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






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






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






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






20. 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.






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






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






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






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






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






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






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






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






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






30. 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.






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






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






33. An ERM is not dependent on the ____________.






34. 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.






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






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






37. 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.






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






39. Data redundancy produces ____.






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






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






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






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






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






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






46. A ___________ must not contain a repeating group .






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






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






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






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