Test your basic knowledge |

Data Modeling

Subject : it-skills
Instructions:
  • Answer 50 questions in 30 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. An ERM is not dependent on the ____________.






2. Another word for existence-independent is ____.






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






4. 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.






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






6. 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 ____.






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






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






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






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






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






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






13. ____ yields better performance.






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






15. 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.






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






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






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






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






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






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






22. 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.






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






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






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






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






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






28. A ______ attribute can have only one value.






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






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






31. Improving ___ leads to more flexible queries.






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






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






34. 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.






35. 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.






36. 1NF - 2NF - and 3NF are _____.






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






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






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






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






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






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






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






44. A ___________ must not contain a repeating group .






45. 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 ____.






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






47. Data redundancy produces ____.






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






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






50. 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.