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. ________ cannot be further subdivided.






2. An ERM is not dependent on the ____________.






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






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






5. 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.






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






7. Improving ___ leads to more flexible queries.






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






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






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






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






12. A ___________ must not contain a repeating group .






13. 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.






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






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






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






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






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






19. 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.






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






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






22. 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.






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






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






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






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






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






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






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






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






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






33. 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.






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






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






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






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






38. Data redundancy produces ____.






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






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






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






42. ____ yields better performance.






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






44. A ______ attribute can have only one value.






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






46. 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 ____.






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






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






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






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