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






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






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






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






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






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






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






8. 1NF - 2NF - and 3NF are _____.






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






10. 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.






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






12. 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.






13. ________ cannot be further subdivided.






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






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






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






17. Another word for existence-independent is ____.






18. 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 ____.






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






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






21. 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.






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






23. A ___________ must not contain a repeating group .






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






25. 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.






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






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






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






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






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






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






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






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






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






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






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






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






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






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






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






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






42. Improving ___ leads to more flexible queries.






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






44. An ERM is not dependent on the ____________.






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






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






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






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






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






50. 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.