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






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






3. 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.






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






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






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






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






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






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






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






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






12. Data redundancy produces ____.






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






14. Improving ___ leads to more flexible queries.






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






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






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






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






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






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






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






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






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






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






25. 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.






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






27. ____ yields better performance.






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






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






30. 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.






31. 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.






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






33. 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.






34. 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.






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






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






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






38. A ___________ must not contain a repeating group .






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






40. An ERM is not dependent on the ____________.






41. 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 ____.






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






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






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






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






46. 1NF - 2NF - and 3NF are _____.






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






48. Another word for existence-independent is ____.






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






50. 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.