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. Need not be stored physically in the data base.






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






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






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






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






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






7. An ERM is not dependent on the ____________.






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






9. 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.






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






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






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






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






14. Another word for existence-independent is ____.






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






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






17. 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 ____.






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






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






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






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






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






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






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






25. 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.






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






27. 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.






28. ____ yields better performance.






29. 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.






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






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






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






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






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






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






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






37. A ___________ must not contain a repeating group .






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






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






40. Data redundancy produces ____.






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






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






43. 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.






44. 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 ____.






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






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






47. 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.






48. ________ cannot be further subdivided.






49. 1NF - 2NF - and 3NF are _____.






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