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






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






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






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






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






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






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






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






9. Improving ___ leads to more flexible queries.






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






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






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






13. 1NF - 2NF - and 3NF are _____.






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






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






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






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






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






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






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






21. ________ cannot be further subdivided.






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






23. 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.






24. ____ yields better performance.






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






26. A ___________ must not contain a repeating group .






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






28. 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.






29. 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 ____.






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






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






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






33. A ______ attribute can have only one value.






34. Data redundancy produces ____.






35. 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.






36. 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.






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






38. 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.






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






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






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






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






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






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






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






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






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






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






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