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






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






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






4. 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.






5. Improving ___ leads to more flexible queries.






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






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






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






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






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






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






12. 1NF - 2NF - and 3NF are _____.






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






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






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






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






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






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






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






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






21. 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.






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






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






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






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






26. Another word for existence-independent is ____.






27. 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 ____.






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






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






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






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






32. 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.






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






34. Data redundancy produces ____.






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






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






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






38. An ERM is not dependent on the ____________.






39. 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.






40. A ___________ must not contain a repeating group .






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






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






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






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






45. ________ cannot be further subdivided.






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






47. ____ yields better performance.






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






49. A ______ attribute can have only one value.






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