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






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






3. 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.






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






5. 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 ____.






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






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






8. 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.






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






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






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






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






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






14. Data redundancy produces ____.






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






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






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






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






20. A ______ attribute can have only one value.






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






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






23. 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.






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






25. 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.






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






27. 1NF - 2NF - and 3NF are _____.






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






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






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






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






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






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






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






35. A ___________ must not contain a repeating group .






36. 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 ____.






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






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






39. Improving ___ leads to more flexible queries.






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






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






42. Another word for existence-independent is ____.






43. ____ yields better performance.






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






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






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






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






48. An ERM is not dependent on the ____________.






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






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