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 ___ identifier is composed of more than one attribute.






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






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






4. A ______ attribute can have only one value.






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






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






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






8. ____ yields better performance.






9. 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.






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






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






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






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






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






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. ________ cannot be further subdivided.






17. 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.






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






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






20. 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 ____.






21. 1NF - 2NF - and 3NF are _____.






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






23. An ERM is not dependent on the ____________.






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






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






26. Improving ___ leads to more flexible queries.






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






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






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






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






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






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






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






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






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






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






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






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






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






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






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






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






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






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






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






47. A ___________ must not contain a repeating group .






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






49. 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.






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