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






3. 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.






4. 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 ____.






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






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






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






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






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






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






11. 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.






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






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






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






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






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






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






18. ________ cannot be further subdivided.






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






20. A ______ attribute can have only one value.






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






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






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






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






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






26. 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.






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






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






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






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






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






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






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






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






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






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






37. 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.






38. Data redundancy produces ____.






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






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






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






42. Improving ___ leads to more flexible queries.






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






44. 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 ____.






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






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






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






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






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






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