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. 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.






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






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






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






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






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






7. 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.






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






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






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






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






12. 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 ____.






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






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






15. Another word for existence-independent is ____.






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






17. 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.






18. ________ cannot be further subdivided.






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






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






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






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






23. 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.






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






25. 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.






26. Data redundancy produces ____.






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






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






29. Improving ___ leads to more flexible queries.






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






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






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






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






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






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






36. 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.






37. 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.






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






39. ____ yields better performance.






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






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






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






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






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






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






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






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






48. An ERM is not dependent on the ____________.






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






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