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






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






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






4. 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.






5. 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.






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






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






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






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






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






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






12. 1NF - 2NF - and 3NF are _____.






13. A ___________ must not contain a repeating group .






14. A ___ identifier is composed of more than one attribute.






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






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






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






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






19. ________ cannot be further subdivided.






20. Another word for existence-independent is ____.






21. 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.






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






23. 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.






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






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






26. 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.






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






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






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






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






31. ____ yields better performance.






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






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






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






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






36. An ERM is not dependent on the ____________.






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






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






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






41. Data redundancy produces ____.






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






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






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






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






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






47. 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.






48. Improving ___ leads to more flexible queries.






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






50. 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.