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






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






3. Improving ___ leads to more flexible queries.






4. 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.






5. 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 ____.






6. ____ yields better performance.






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






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






9. 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.






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






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






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






13. 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 ____.






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






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






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






17. A ___________ must not contain a repeating group .






18. A ______ attribute can have only one value.






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






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






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






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






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






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






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






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






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






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






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






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






31. 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.






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






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






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






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






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






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






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






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






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






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






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






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






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






45. 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.






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






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






48. 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.






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






50. Another word for existence-independent is ____.