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. 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.






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






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






4. 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 ____.






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






6. 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.






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






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






9. 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.






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






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






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






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






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






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






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






17. Data redundancy produces ____.






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






19. 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.






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






21. A ___________ must not contain a repeating group .






22. 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.






23. An ERM is not dependent on the ____________.






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






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






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






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






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






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






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






31. ____ yields better performance.






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






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






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






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






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






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






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






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






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






41. Another word for existence-independent is ____.






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






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






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






45. A ______ attribute can have only one value.






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






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






48. 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.






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






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