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






2. A ______ attribute can have only one value.






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






4. ____ yields better performance.






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






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






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






8. 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.






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






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






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






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






13. ________ cannot be further subdivided.






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






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






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






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






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






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






20. Another word for existence-independent is ____.






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






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






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






24. 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.






25. 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.






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






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






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






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






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






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






32. Improving ___ leads to more flexible queries.






33. 1NF - 2NF - and 3NF are _____.






34. Data redundancy produces ____.






35. 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.






36. An ERM is not dependent on the ____________.






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






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






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






40. 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.






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






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






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






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






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






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






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






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






49. A ___________ must not contain a repeating group .






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