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






3. Another word for existence-independent is ____.






4. ____ yields better performance.






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






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






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






8. 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.






9. An ERM is not dependent on the ____________.






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






11. 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.






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






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






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






15. 1NF - 2NF - and 3NF are _____.






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






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






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






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






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






21. Improving ___ leads to more flexible queries.






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






23. A ___________ must not contain a repeating group .






24. 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.






25. ________ cannot be further subdivided.






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






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






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






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






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






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






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






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






34. 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 ____.






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






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






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






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






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






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






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






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






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






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






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






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






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






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






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






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