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. 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.






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






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






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






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






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






7. Improving ___ leads to more flexible queries.






8. 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.






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






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






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






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






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






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






15. 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.






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






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






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






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






20. 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.






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






22. 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.






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






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






25. Data redundancy produces ____.






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






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






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






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






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






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






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






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






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






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






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






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






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






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






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






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






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






43. 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.






44. 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.






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






46. 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 ____.






47. ________ cannot be further subdivided.






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






49. ____ yields better performance.






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