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






2. 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.






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






4. 1NF - 2NF - and 3NF are _____.






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






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






7. 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.






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






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






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






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






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






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






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






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






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






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






18. An ERM is not dependent on the ____________.






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






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






21. ____ yields better performance.






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






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






24. 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.






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






26. Data redundancy produces ____.






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






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






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






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






31. 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 ____.






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






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






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






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






36. Another word for existence-independent is ____.






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






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






39. ________ cannot be further subdivided.






40. 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.






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






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






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






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






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






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






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. 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.






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






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