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






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






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






4. 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.






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






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






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






8. An ERM is not dependent on the ____________.






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






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






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






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






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






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






15. 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.






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






17. Another word for existence-independent is ____.






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






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






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






21. 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.






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






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






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






25. 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.






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






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






28. 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.






29. A ______ attribute can have only one value.






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






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






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






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






34. A ___________ must not contain a repeating group .






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






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






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






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






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






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






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. Need not be stored physically in the data base.






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






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






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






46. ____ yields better performance.






47. 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.






48. 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 ____.






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






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