DBMS Chapter 4: Logical Database Design and the Relational Model
A primary key that consists of more than one attribute is called a: (A) composite key. (B) multivalued key. (C) cardinal key. (D) foreign key.
A. composite key
The attribute on the left-hand side of the arrow in a functional dependency is the: (A) determinant. (B) candidate key. (C) foreign key. (D) primary key.
A. determinant
A domain definition consists of the following components EXCEPT: (A) integrity constraints. (B) size. (C) data type. (D) domain name.
A. integrity constraints
A rule that states that each foreign key value must match a primary key value in the other relation is called the: (A) referential integrity constraint. (B) key match rule. (C) foreign/primary match rule. (D) entity key group rule.
A. referential integrity constraint
An attribute (or attributes) that uniquely identifies each row in a relation is called a: (A) foreign field. (B) primary key. (C) duplicate key. (D) column.
B. Primary key
Which of the following is NOT a reason to create an instance of a relational schema with sample data? (A) Sample data can be used for prototype generation. (B) Sample data can reverse database implementation errors. (C) Sample data provide a convenient way to check the accuracy of your design. (D) Sample data can be used to improve user communications.
B. Sample data can reverse database implementation errors.
An alternative name for an attribute is called a(n): (A) related characteristic. (B) alias. (C) alternate attribute. (D) synonym.
B. alias
In the SQL language, the ________ statement is used to make table definitions. (A) create index (B) create table (C) create session (D) select
B. create table
A constraint between two attributes is called a(n): (A) attribute dependency. (B) functional dependency. (C) functional relation. (D) functional relation constraint.
B. functional dependency
A functional dependency in which one or more nonkey attributes are functionally dependent on part, but not all, of the primary key is called a ________ dependency. (A) merged relation (B) partial functional (C) partial key-based (D) cross key
B. partial functional
A functional dependency between two or more nonkey attributes is called a: (A) partial nonkey dependency. (B) transitive dependency. (C) partial functional dependency. (D) partial transitive dependency.
B. transitive dependency
Understanding the steps involved in transforming EER diagrams into relations is important because: (A) there are rarely legitimate alternatives from which to choose. (B) CASE tools can model any situation. (C) you must be able to check the output of a CASE tool. (D) none of the above.
C, you must be bale ot check the output of a CASE tool.
A relation that contains no multivalued attributes, and has nonkey attributes solely dependent on the primary key, but contains transitive dependencies is in which normal form? (A) Fourth (B) First (C) Second (D) Third
C. Second
When a regular entity type contains a multivalued attribute, one must: (A) create two new relations, both containing the multivalued attribute. (B) create a single relation with multiple lines for each instance of the multivalued attribute. (C) create two new relations, one containing the multivalued attribute. (D) none of the above.
C. create two new relations, one containing the multivalued attribute
A nonkey attribute is also called a(n): (A) unimportant datum. (B) column. (C) descriptor. (D) address.
C. descriptor
A primary key whose value is unique across all relations is called a(n): (A) foreign global key. (B) global primary key. (C) enterprise key. (D) inter-table primary key.
C. enterprise key
The entity integrity rule states that: (A) each entity must have a primary key. (B) a primary key must have only one attribute. (C) no primary key attribute can be null. (D) referential integrity must be maintained across all entities.
C. no primary key attribute can be null.
A two-dimensional table of data is called a: (A) set. (B) group. (C) relation. (D) declaration.
C. relation
Two or more attributes having different names but the same meaning are called: (A) homonyms. (B) alternate attributes. (C) synonyms. (D) aliases.
C. synonym
A candidate key must satisfy all of the following conditions EXCEPT: (A) the key must uniquely identify the row. (B) each nonkey attribute is functionally dependent upon it. (C) the key must indicate the row's position in the table. (D) the key must be nonredundant.
C. the key must indicate the row's position in the table.
A relation that contains minimal redundancy and allows easy use is considered to be: (A) clean. (B) simple. (C) well-structured. (D) complex.
C. well-structured
Physical database design decisions must be made carefully because of impacts on: (A) data accessibility. (B) security. (C) response times. (D) all of the above.
D. All o the above
Which of the following are properties of relations? (A) No two rows in a relation are identical. (B) Each attribute has a unique name. (C) There are no multivalued attributes in a relation. (D) All of the above.
D. All of the above
________ is a component of the relational data model included to specify business rules to maintain the integrity of data when they are manipulated. (A) Business integrity (B) Data structure (C) Business rule constraint (D) Data integrity
D. Data integrity.
An understanding of how to merge relation is important because: (A) different views may need to be integrated. (B) new data requirements may produce new relations to be merged. (C) there may be a need to merge relations on projects with subteams. (D) all of the above.
D. all of the above
The relational data model consists of which components? (A) Data integrity (B) Data manipulation (C) Data structure (D) All of the above
D. all of the above
Which of the following anomalies result from a transitive dependency? (A) Deletion (B) Modification (C) Insertion (D) All of the above
D. all of the above
Which of the following are anomalies that can be caused by redundancies in tables? (A) Deletion (B) Insertion (C) Modification (D) All of the above
D. all of the above
An attribute in a relation of a database that serves as the primary key of another relation in the same database is called a: (A) foreign attribute. (B) link key. (C) link attribute. (D) foreign key.
D. foreign key
An attribute that may have more than one meaning is called a(n): (A) alias. (B) double defined attribute. (C) synonym. (D) homonym.
D. homonym
A form of database specification that indicates all the parameters for data storage that are then input to database implementation is: (A) schematic. (B) conceptual. (C) logical. (D) physical.
D. physical