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. 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.






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






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






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






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






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






7. 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 ____.






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






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






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






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






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






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






14. A ______ attribute can have only one value.






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






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






17. 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.






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






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






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






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






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






23. ________ cannot be further subdivided.






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






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






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






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






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






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






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






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






32. 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.






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






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






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






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






37. Another word for existence-independent is ____.






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






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






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






41. Data redundancy produces ____.






42. 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.






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






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






45. Improving ___ leads to more flexible queries.






46. 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.






47. ____ yields better performance.






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






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






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