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






2. Improving ___ leads to more flexible queries.






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






4. 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.






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






6. 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.






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






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






9. A ______ attribute can have only one value.






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






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






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






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






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






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






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






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






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






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






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






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






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






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






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






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






27. 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 ____.






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






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






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






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






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






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






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






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






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






37. 1NF - 2NF - and 3NF are _____.






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






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






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






41. A ___________ must not contain a repeating group .






42. 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.






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






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






45. An ERM is not dependent on the ____________.






46. 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.






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






48. In the ERD - Cardinality is indicated using the ___ notation.






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






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