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 ___ attribute is one that cannot be subdivided.






2. 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.






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






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






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






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






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






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






9. 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 ____.






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






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






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






13. 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.






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






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






16. ________ cannot be further subdivided.






17. 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.






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






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






21. Data redundancy produces ____.






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






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






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






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






26. 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 ____.






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






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






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






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






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






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






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






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






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






37. A ___________ must not contain a repeating group .






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






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






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






41. 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.






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






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






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






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






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






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






48. An ERM is not dependent on the ____________.






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






50. Improving ___ leads to more flexible queries.