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. 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.






2. Improving ___ leads to more flexible queries.






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






4. ____ yields better performance.






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






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






7. 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.






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






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






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






11. Another word for existence-independent is ____.






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






13. A ___________ must not contain a repeating group .






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






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






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






17. 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.






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






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






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






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






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






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






24. 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.






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






26. ________ cannot be further subdivided.






27. The conflicts between design efficiency - ____________ - and processing speed are often resolved through compromised that include denormalization.






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






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






30. 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 ____.






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






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






33. 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 ____.






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






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






36. An ERM is not dependent on the ____________.






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






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






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






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






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






42. 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.






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






44. A ______ attribute can have only one value.






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






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






47. 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.






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






49. 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.






50. 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.