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. 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.






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






3. 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.






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






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






6. ____ yields better performance.






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






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






9. Improving ___ leads to more flexible queries.






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






11. An ERM is not dependent on the ____________.






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






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






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






15. 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 ____.






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






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






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






19. 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 ____.






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






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






22. 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.






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






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






25. 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.






26. A ______ attribute can have only one value.






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






28. 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.






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






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






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






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






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






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






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






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






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






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






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






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






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






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






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






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






46. 1NF - 2NF - and 3NF are _____.






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






48. For most business transactional databases - we should normalize relations into ____.






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






50. A ___________ must not contain a repeating group .