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. A ______ attribute can have only one value.






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






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






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






5. Data redundancy produces ____.






6. 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.






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






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






9. 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 ____.






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






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






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






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






14. 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.






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






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






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






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






19. 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.






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






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






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






23. 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.






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






25. 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.






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






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






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






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






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






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






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






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






34. Improving ___ leads to more flexible queries.






35. An ERM is not dependent on the ____________.






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






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






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






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






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






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






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






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






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






45. ____ yields better performance.






46. Another word for existence-independent is ____.






47. 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.






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






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






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