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 ___ attribute is one that cannot be subdivided.






2. A ______ attribute can have only one value.






3. 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.






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






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






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






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






8. 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.






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






10. An ERM is not dependent on the ____________.






11. 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.






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






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






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






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






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






17. 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.






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






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






20. ________ cannot be further subdivided.






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






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






23. 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 ____.






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






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






26. 1NF - 2NF - and 3NF are _____.






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






28. Data redundancy produces ____.






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






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






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






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






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






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






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






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






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






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






39. 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 ____.






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






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






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






43. ____ yields better performance.






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






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






46. Improving ___ leads to more flexible queries.






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






48. 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.






49. 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.






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