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






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






3. 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.






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






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






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






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






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






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






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






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






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






13. A ______ attribute can have only one value.






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






15. 1NF - 2NF - and 3NF are _____.






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






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






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






19. 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 ____.






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






21. Another word for existence-independent is ____.






22. 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.






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






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






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






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






27. Data redundancy produces ____.






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






29. 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.






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






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






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






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






34. 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.






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






36. ____ yields better performance.






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






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






39. A ___________ must not contain a repeating group .






40. 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.






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






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






43. 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.






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






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






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






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






48. ________ cannot be further subdivided.






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






50. 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.