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






2. 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.






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






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






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






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






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






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






9. An ERM is not dependent on the ____________.






10. 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.






11. Improving ___ leads to more flexible queries.






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






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






14. 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.






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






16. The associative entity is also known as a ___ entity.






17. 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.






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






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






20. ________ cannot be further subdivided.






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






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






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






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






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






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






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






28. 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.






29. 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 ____.






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






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






32. Another word for existence-independent is ____.






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






34. 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.






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






36. 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 ____.






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






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






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






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






41. 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.






42. A ___________ must not contain a repeating group .






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






44. 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.






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






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






47. Data redundancy produces ____.






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






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






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