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






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






3. 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.






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






5. 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.






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






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






8. 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.






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






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






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






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






13. A ______ attribute can have only one value.






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






15. A ___________ must not contain a repeating group .






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






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






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






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






20. 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.






21. Data redundancy produces ____.






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






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






24. Improving ___ leads to more flexible queries.






25. 1NF - 2NF - and 3NF are _____.






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






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






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






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






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






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






32. 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 ____.






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






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






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






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






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






38. ________ cannot be further subdivided.






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






40. 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.






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






42. An ERM is not dependent on the ____________.






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






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






45. 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 ____.






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






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






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






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






50. 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.