Chapter 6 Designing Database
8. Which of the following is correct in reference to a database? A database can support up to three logical views. A database can support only one logical view. A database can support many logical views. A database can support many physical views.
A database can support many logical views.
5. What is a primary key? A field (or group of fields) that uniquely identifies a given entity in a table A primary key of one table that appears as an attribute in another table and acts to provide a logical relationship among the two tables A field (or group of fields) that uniquely identifies a given attribute in a table A characteristic or property of an entity
A field (or group of fields) that uniquely identifies a given entity in a table
1. Which of the following database structures stores information in a tree-like structure that allows repeating information using parent/child relationships, in such a way that it cannot have too many relationships? Hierarchical database Network database Relational database model All of these
Hierarchical database
7. All of the following are advantages of database-stored information, except which of the following? Increased information integrity Increased information redundancy Increased performance Increased flexibility
Increased information redundancy
10. What are the rules that help ensure the quality of information? Business-critical integrity constraints Information integrity Relational integrity constraints Integrity constraints
Integrity constraints
4. Why do relational databases use primary keys and foreign keys? To create physical relationships All of these To create logical relationships To create a database
To create logical relationships
6. What is a foreign key? A field (or group of fields) that uniquely identifies a given entity in a table A characteristic or property of an entity A field (or group of fields) that uniquely identifies a given attribute in a table A primary key of one table that appears as an attribute in another table and acts to provide a logical relationship among the two tables
A primary key of one table that appears as an attribute in another table and acts to provide a logical relationship among the two tables
2. In the relational database model, what is a person, place, thing, transaction, or event about which information is stored? Physical view Logical view Attribute Entity
Entity
3. What are characteristics or properties of an entity called? Columns Attributes All of these Fields
All of these
9. What is the primary problem with redundant information? It is difficult to determine which values are the most current. It is often inconsistent. All of these. It is difficult to determine which values are the most accurate.
All of these.
