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. Another word for existence-independent is ____.






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






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






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






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






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






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






8. 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.






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






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






11. 1NF - 2NF - and 3NF are _____.






12. 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.






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






14. Improving ___ leads to more flexible queries.






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






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






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






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






19. 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.






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






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






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






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






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






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






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






27. 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 ____.






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






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






30. 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.






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






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






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






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






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






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






37. A ______ attribute can have only one value.






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






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






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






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






42. ____ yields better performance.






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






44. 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.






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






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






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






48. 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.






49. Data redundancy produces ____.






50. A ___________ must not contain a repeating group .