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






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






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






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






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






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






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






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






10. 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.






11. A ______ attribute can have only one value.






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






13. 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.






14. 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 ____.






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






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






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






18. 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.






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






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






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






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






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






24. 1NF - 2NF - and 3NF are _____.






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






26. ________ cannot be further subdivided.






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






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






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






30. ____ yields better performance.






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






32. A ___________ must not contain a repeating group .






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






34. 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.






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






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 ___ attribute is one that cannot be subdivided.






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






39. 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.






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






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






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






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






44. An ERM is not dependent on the ____________.






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






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






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






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






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