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 ____ 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.






2. A ___________ must not contain a repeating group .






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






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






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






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






7. An ERM is not dependent on the ____________.






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






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






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






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






12. 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.






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






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






15. 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.






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






17. 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 ____.






18. ________ cannot be further subdivided.






19. 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 ____.






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






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






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






23. 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.






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






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






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






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






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






29. 1NF - 2NF - and 3NF are _____.






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






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






32. 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.






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






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






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






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






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






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






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






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






41. 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.






42. Another word for existence-independent is ____.






43. Data redundancy produces ____.






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






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






46. ____ yields better performance.






47. 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.






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






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






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