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






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






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






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






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






6. 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.






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






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






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






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






11. 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.






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






13. 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.






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






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






16. A ___________ must not contain a repeating group .






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






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






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






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






21. 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.






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






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






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






25. 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.






26. 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 ____.






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






28. Another word for existence-independent is ____.






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






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






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






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






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






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






35. ________ cannot be further subdivided.






36. ____ yields better performance.






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






38. Improving ___ leads to more flexible queries.






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






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






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






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






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






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






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. An ERM is not dependent on the ____________.






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






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






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






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