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






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






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






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






6. A ______ attribute can have only one value.






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






8. 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.






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






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






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






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






13. ____ yields better performance.






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






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






16. 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.






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






19. 1NF - 2NF - and 3NF are _____.






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






21. The existence of a(n) ___ relationship indicated that the minimum cardinality is at least 1 for the mandatory entity.






22. 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.






23. An ERM is not dependent on the ____________.






24. 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 ____.






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






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






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






28. Data redundancy produces ____.






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






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






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






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






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






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






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






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






37. 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.






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






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






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






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






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






43. A ___________ must not contain a repeating group .






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






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






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






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






48. Improving ___ leads to more flexible queries.






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






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