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






2. Improving ___ leads to more flexible queries.






3. A ___________ must not contain a repeating group .






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






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






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






7. 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.






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






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






10. A ______ attribute can have only one value.






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






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






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






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






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






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






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






18. 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.






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






20. 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.






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






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






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






24. 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.






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






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






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






28. 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.






29. ________ cannot be further subdivided.






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






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






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






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






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






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






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






37. 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.






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






39. 1NF - 2NF - and 3NF are _____.






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






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






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






43. Another word for existence-independent is ____.






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






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






46. An ERM is not dependent on the ____________.






47. 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 ____.






48. 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 ____.






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






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