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






2. 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.






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






4. 1NF - 2NF - and 3NF are _____.






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






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






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






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






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






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






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






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






13. Another word for existence-independent is ____.






14. 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.






15. A ______ attribute can have only one value.






16. 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.






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






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






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






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






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






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






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






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






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






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






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






28. ________ cannot be further subdivided.






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






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






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






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






33. A ___________ must not contain a repeating group .






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






35. 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.






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






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






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






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






40. Data redundancy produces ____.






41. 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.






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






43. 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 ____.






44. 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.






45. An ERM is not dependent on the ____________.






46. Improving ___ leads to more flexible queries.






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






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






49. 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.






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