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






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






4. 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.






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






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






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






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






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






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






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






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






13. An ERM is not dependent on the ____________.






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






15. 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.






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






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






18. Another word for existence-independent is ____.






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






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






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






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






23. Improving ___ leads to more flexible queries.






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






25. A ______ attribute can have only one value.






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






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






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






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






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






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






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






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






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






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






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






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






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






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






40. A ___________ must not contain a repeating group .






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






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






43. Data redundancy produces ____.






44. 1NF - 2NF - and 3NF are _____.






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






46. ____ yields better performance.






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






48. ________ cannot be further subdivided.






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






50. 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.