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






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






3. Data redundancy produces ____.






4. Another word for existence-independent is ____.






5. A ______ attribute can have only one value.






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






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






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






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






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






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






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






13. 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.






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






15. 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.






16. ____ yields better performance.






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






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






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






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






21. 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.






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






23. 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.






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






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






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






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






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






29. Improving ___ leads to more flexible queries.






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






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






32. 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 ____.






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






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






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






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






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






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






39. ________ cannot be further subdivided.






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






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






42. 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 ____.






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






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






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






46. 1NF - 2NF - and 3NF are _____.






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






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






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






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