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






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






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






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






5. 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.






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






7. A ______ attribute can have only one value.






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






9. Improving ___ leads to more flexible queries.






10. ____ yields better performance.






11. 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 ____.






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






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






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






15. 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.






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






17. Data redundancy produces ____.






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






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






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






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






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






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






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






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






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






27. 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 ____.






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






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






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






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






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






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






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






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






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






37. An ERM is not dependent on the ____________.






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






39. 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.






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






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






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






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






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






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






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






48. 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.






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






50. A ___________ must not contain a repeating group .