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






2. 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.






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






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






5. A ______ attribute can have only one value.






6. 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.






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






8. An ERM is not dependent on the ____________.






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






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






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






12. Improving ___ leads to more flexible queries.






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






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






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






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






17. 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.






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






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






20. Data redundancy produces ____.






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






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






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






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






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






26. 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.






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






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






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






30. Another word for existence-independent is ____.






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






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






33. 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.






34. 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.






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






36. 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.






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






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






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






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






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






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






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






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






45. A table that has all key attributes defined - has no repeating groups - and all its attributes are dependent on the primary key - is said to be in ____.






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






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






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






49. 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 ____.






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