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. Another word for existence-independent is ____.






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






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






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






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






6. A ___________ must not contain a repeating group .






7. 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.






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






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






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






11. 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.






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






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






14. ________ cannot be further subdivided.






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






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






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






18. Improving ___ leads to more flexible queries.






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






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






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






23. ____ yields better performance.






24. 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.






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






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






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






28. Data redundancy produces ____.






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






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






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






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






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






34. 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 ____.






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






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






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






38. An ERM is not dependent on the ____________.






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






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






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






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






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






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






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






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






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






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






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






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