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






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






4. ____ yields better performance.






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






6. Improving ___ leads to more flexible queries.






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






8. Another word for existence-independent is ____.






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






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






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






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






13. 1NF - 2NF - and 3NF are _____.






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






15. ________ cannot be further subdivided.






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






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






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






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






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






21. A ___________ must not contain a repeating group .






22. 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.






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






25. 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.






26. 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.






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






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






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






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






31. A ______ attribute can have only one value.






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






33. 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.






34. 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.






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






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






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






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






39. 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 ____.






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






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






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






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






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






45. An ERM is not dependent on the ____________.






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






47. 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.






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






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






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