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






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






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






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






5. 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.






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






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






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






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






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






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






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






13. 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.






14. ________ cannot be further subdivided.






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






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






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






18. 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 ____.






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






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






21. 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.






22. 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.






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






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






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






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






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






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






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






30. Another word for existence-independent is ____.






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






32. 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.






33. Data redundancy produces ____.






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






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






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






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






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






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






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






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






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






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






45. Improving ___ leads to more flexible queries.






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






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






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






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






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