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 ___ derives its name from the fact that a group of multiple entries of the same type can exist for any single key attribute occurrence.






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






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






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






6. A ___________ must not contain a repeating group .






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






8. 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.






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






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






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






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






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






14. Another word for existence-independent is ____.






15. An ERM is not dependent on the ____________.






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






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






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






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






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






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






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






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






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






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






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






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






28. Data redundancy produces ____.






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






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






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






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






33. 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.






34. Improving ___ leads to more flexible queries.






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






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






37. ____ yields better performance.






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






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






40. 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 ____.






41. 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.






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






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






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






45. 1NF - 2NF - and 3NF are _____.






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






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






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






49. A ______ attribute can have only one value.






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