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






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






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






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






5. 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.






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






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






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






9. 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.






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






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






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






13. 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.






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






15. 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.






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






17. 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 ____.






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






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






20. A ___________ must not contain a repeating group .






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






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






23. ____ yields better performance.






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






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






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






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






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






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






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






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






34. An ERM is not dependent on the ____________.






35. Another word for existence-independent is ____.






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






37. 1NF - 2NF - and 3NF are _____.






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






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






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






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






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






43. 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.






44. Data redundancy produces ____.






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






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






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






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






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






50. 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 ____.