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






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






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






4. 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.






5. Data redundancy produces ____.






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






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






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






9. ________ cannot be further subdivided.






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






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






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






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






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






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






16. 1NF - 2NF - and 3NF are _____.






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






18. 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.






19. 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 ____.






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






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






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






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






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






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






26. Another word for existence-independent is ____.






27. 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.






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






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






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






31. 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.






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






33. An example of denormalization is using a ___ denormalized table to hold report data. This is required when creating a tabular report in which the columns represent data that is stored in the table as rows.






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






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






36. 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.






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






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






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






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






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






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






43. ____ yields better performance.






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






45. 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.






46. An ERM is not dependent on the ____________.






47. Improving ___ leads to more flexible queries.






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






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






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