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






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






3. A ___________ must not contain a repeating group .






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






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






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






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






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






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






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






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






12. 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.






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. A ___ relationship exists when two entities are associated.






15. A ______ attribute can have only one value.






16. 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 ____.






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






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






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






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






21. ____ yields better performance.






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






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






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






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






26. 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.






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






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






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






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






31. Another word for existence-independent is ____.






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






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






34. 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 ____.






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






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






37. 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.






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






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






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






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






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






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






44. ________ cannot be further subdivided.






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






46. 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.






47. 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.






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






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






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