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






2. 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.






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






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






5. 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.






6. 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.






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






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






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






10. 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 ____.






11. 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.






12. A ___________ must not contain a repeating group .






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






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






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






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






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






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






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






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






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






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






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






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






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






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






27. Improving ___ leads to more flexible queries.






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






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






30. 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.






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






32. A ______ attribute can have only one value.






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






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






35. ____ yields better performance.






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






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






38. 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 ____.






39. An ERM is not dependent on the ____________.






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






41. ________ cannot be further subdivided.






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






43. Another word for existence-independent is ____.






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






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






46. 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.






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






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






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






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