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 MOST LIKELY DATA TYPE FOR A SURROGATE KEY IS ____.






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






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






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






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






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






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






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






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






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






11. Data redundancy produces ____.






12. Improving ___ leads to more flexible queries.






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






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






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






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






17. 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.






18. 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.






19. A ______ attribute can have only one value.






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






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






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






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






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






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






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






27. 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.






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






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






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 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 ____.






32. An ERM is not dependent on the ____________.






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






34. 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.






35. 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 ____.






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






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






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






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






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






41. ________ cannot be further subdivided.






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






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






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






45. 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.






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






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






48. ____ yields better performance.






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






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