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






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






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






4. 1NF - 2NF - and 3NF are _____.






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






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






7. 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 ____.






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






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






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






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






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






13. 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.






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






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






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






17. Data redundancy produces ____.






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






19. Another word for existence-independent is ____.






20. 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.






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






22. 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.






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






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






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






26. A ___________ must not contain a repeating group .






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






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






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






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






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






32. A ______ attribute can have only one value.






33. 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 ____.






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






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






36. 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.






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






38. ________ cannot be further subdivided.






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






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






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






42. Improving ___ leads to more flexible queries.






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






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






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






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






47. 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.






48. 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.






49. ____ yields better performance.






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