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






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






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






4. 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 ____.






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






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






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






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






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






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






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






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






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






14. 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.






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






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






17. Improving ___ leads to more flexible queries.






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






19. 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.






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






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






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






23. 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 ____.






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






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






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






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






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






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






30. 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.






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






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






33. A ______ attribute can have only one value.






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






35. 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.






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






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






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






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






40. 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.






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






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






43. 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.






44. Another word for existence-independent is ____.






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






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






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






48. ____ yields better performance.






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






50. 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.