Q&A Hero

Q: Referential ____ means that if the foreign key contains a value, that value refers to an existing valid tuple (row) in another relation.a. integrity b. uniqueness c. directiond. relations

Q: Controlled ____ makes a relational database work.a. relations b. logic c. chaosd. redundancy

Q: No data entry at all is known as a(n) ____.a. nil b. null c. emptyd. zero

Q: A ____ is any key that uniquely identifies each row.a. superkey b. special c. selectived. candidate

Q: Any attribute that is part of a key is known as a ____.a. key attributeb. logical attribute c. key determinerd. selector

Q: The attribute B is ____ the attribute A if each value in column A determines one and only one value in column B.a. logically dependent on b. owned by c. determined byd. functionally dependent on

Q: In the context of a database table, the statement "A ____ B" indicates that if you know the value of attribute A, you can look up the value of attribute B.a. contains b. is related to c. ownsd. determines

Q: In the relational model, ____ are important because they are used to ensure that each row in a table is uniquely identifiable.a. relations b. keys c. indexesd. logical structures

Q: ____ data can have only a true or false (yes or no) values.a. Logical b. Character c. Dated. Numeric

Q: Date attributes contain calendar dates stored in a special format known as the ____ date format.a. Epoch b. Calendar c. Juliand. logical

Q: A(n) ____ is perceived as a two-dimensional structure composed of rows and columns.a. table b. rowset c. attributed. intersection

Q: The relational model's creator, E. F. Codd, used the term relation as a synonym for ____.a. indexb. key c. tabled. relationship

Q: The relational database model enables you to view data ____ rather than ____.a. relationally, hierarchically b. hierarchically, relationally c. physically, logicallyd. logically, physically

Q: ____ logic, used extensively in mathematics, provides a framework in which an assertion (statement of fact) can be verified as either true or false.a. Predicate b. Database c. Relationald. Index

Q: DBMSs use indexes for many different purposes.

Q: As rare as 1:1 relationships should be, certain conditions absolutely requiretheir use.

Q: The one-to-many (1:M) relationship is easily implemented in the relational model by putting the foreign key of the "1" side in the table of the "many" side as a primary key.

Q: Current relational database software generally provides only a system catalog (and not a data dictionary).

Q: A data dictionary is sometimes described as "the database designer's database" because it records the design decisions about tables and their structures.

Q: A data dictionary contains metadatadata about data.

Q: The DIVIDE operation uses one single-column table (e.g., column "a") as the divisor and one two-column table (e.g., columns "a" and "b") as the dividend.

Q: A left outer joinon tables CUSTOMER and AGENT yields all of the rows in the CUSTOMER table, including those that do not have a matching value in the AGENT table.

Q: In a natural join, the column on which the join was made occurs twice in the new table.

Q: The DIFFERENCE operator subtracts one table from the other.

Q: Tables must have the same attribute characteristics (the columns and domains must be compatible) to be used in a UNION.

Q: The SELECT operator yields a vertical subset of a table.

Q: Referential and entity integrity are two names for the same thing.

Q: RDBMSs enforce integrity rules automatically.

Q: A foreign key must exist in both tables that have a relationship.

Q: Describe a conceptual model and its advantages. What is the most widely used conceptual model?

Q: Describe the three parts involved in any SQL-based relational database application.

Q: What are the sources of business rules, and what is the database designer's role with regard to business rules?

Q: What do business rules require to be effective?

Q: What components should an implementation-ready data model contain?

Q: When you can change the internal model without affecting the conceptual model, you have ____________________ independence.

Q: The term ____________________ is used to refer to the task of creating a conceptual data model that could be implemented in any DBMS.

Q: ___________________________________ is a language based on OO concepts that describes a set of diagrams and symbols used to graphically model a system.

Q: In object-oriented terms, a(n) ____________________ defines an object's behavior.

Q: A(n) ____________________ is a collection of similar objects with a shared structure and behavior.

Q: In _________________________, a three-pronged symbol represents the "many" side of the relationship.

Q: In ____________________, relationships are represented by a diamond connected to the related entities through a relationship line.

Q: A(n) ____________________ is a representation of the relational database's entities, the attributes within those entities and the relationships between those entities.

Q: Each column in a relation represents a(n) ____________________.

Q: Each row in a relation is called a(n) ____________________.

Q: The ____________________ defines the portion of the database "seen" by the application programs that produce information from the data.

Q: The ____________________ is the conceptual organization of the entire database as viewed by the database administrator.

Q: A(n) ____________________ in a hierarchical model is the equivalent of a record in a file system.

Q: A(n) ____________________ is a brief, precise, and unambiguous description of a policy, procedure, or principle within a specific organization.

Q: A(n) ____________________ is a relatively simple representation of more complex real-world data structures.

Q: A(n) ____ model represents a global view of the database as viewed by the entire organization.a. external b. conceptual c. internald. physical

Q: The ____ modelis the end users' view of the data environment.a. abstract b. external c. conceptuald. internal

Q: One of the limitations of the ____ model is that there is a lack of standards.a. hierarchical b. network c. relationald. entity relationship

Q: The ____ data model uses the concept of inheritance.a. relational b. network c. object-orientedd. entity relationship

Q: The ____ data model is said to be a semantic data model.a. relationalb. network c. object-orientedd. entity relationship

Q: The ____ model uses the term connectivity to label the relationship types.a. relational c. object-orientedb. network d. entity relationship

Q: The ____ model was developed to allow designers to use a graphical tool to examine structures rather than describing them with text.a. hierarchicalb. network c. object-orientedd. entity relationship

Q: A(n) ____ enables a database administrator to define schema components.a. extensible markup language (XML)b. data definition language (DDL) c. unified modeling language (UML)d. query language

Q: In the ____ model, the user perceives the database as a collection of records in 1:M relationships, where each record can have more than one parent.a. hierarchical b. network c. object-orientedd. entity relationship

Q: The relational data model was developed in the ____.a. 1960s xb. 1970s c. relationald. 1990s

Q: In the ____ model, each parent can have many children, but each child has only one parent.a. hierarchical b. network c. relationald. entity relationship

Q: In the ____ model, the basic logical structure is represented as an upside-down tree.a. hierarchical b. network c. relationald. entity relationship

Q: MySQL is an example of a(n) ____.a. hierarchical model b. file system data model c. relational data modeld. XML data model

Q: Oracle 11g is an example of a(n) ____.a. hierarchical model b. file system data model c. relational data modeld. XML/Hybrid data model

Q: VMS/VSAM is an example of a(n) ____.a. hierarchical model b. file system data model c. relational data modeld. XML data model

Q: The object-oriented data model was developed in the ____.a. 1960s b. 1970s c. 1980sd. 1990s

Q: The hierarchical data model was developed in the ____.a. 1960s b. 1970s c. 1980sd. 1990s

Q: A verb associating two nouns in a business rule translates to a(n) ____ in the data model.a. entity b. attribute c. relationshipd. constraint

Q: A noun in a business rule translates to a(n) ____ in the data model.a. entity b. attribute c. relationshipd. constraint

Q: Which of the following is true of business rules? a. They allow the designer to set company policies with regard to data. b. They allow the designer to develop business processes. c. They can serve as a communication tool between the users and designers. d. They provide a framework for the company's self actualization.

Q: Business rules are derived from ____.a. a detailed description of an organization's operationsb. standards and practices developed over the yearsc. managers' recommendationsd. governmental oversight organization standards

Q: Students and classes have a ____ relationship.a. one-to-one b. one-to-many c. many-to-oned. many-to-many

Q: ____ are normally expressed in the form of rules.a. Attributes b. Entities c. Relationshipsd. Constraints

Q: ____ are important because they help to ensure data integrity.a. Attributes b. Entities c. Relationshipsd. Constraints

Q: A(n) ____ is a restriction placed on the data.a. attribute b. entity c. relationshipd. constraint

Q: A(n) ____ is bidirectional.a. attribute b. entity c. relationshipd. constraint

Q: A(n) ____ is the equivalent of a field in a file system.a. attribute b. entity c. relationshipd. constraint

Q: A(n) ____ is anything about which data are to be collected and stored.a. attribute b. entity c. relationshipd. constraint

Q: A(n) ____ represents a particular type of object in the real world.a. attribute b. entity c. relationshipd. constraint

Q: A(n) ____'s main function is to help you understand the complexities of the real-world environment.a. constraint b. entityc. model d. database

Q: The relational model is hardware-dependent and software-independent.