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






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






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






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






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






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






7. 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.






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






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






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






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






12. 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.






13. 1NF - 2NF - and 3NF are _____.






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






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






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






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






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






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






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






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






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






23. 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.






24. 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 ____.






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






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






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






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






29. 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.






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






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






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






33. Another word for existence-independent is ____.






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






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






36. 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.






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






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






39. 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.






40. Improving ___ leads to more flexible queries.






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






42. 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 ____.






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






44. A ______ attribute can have only one value.






45. ____ yields better performance.






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






47. A ___________ must not contain a repeating group .






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






49. Data redundancy produces ____.






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