Database
For the relationship represented in the figure below, which of the following is true?
A department can have more than one employee.
in the figure shown below, which of the following is true ?
A person can marry at most one person
Which of the following anomalies result from a transitive dependency?
A) Deletion B) Insertion C) Modification
Which of the following are properties of relations?
A) Each attribute has a unique name. B) No two rows in a relation are identical. C) There are no multivalued attributes in a relation.
A requirement to begin designing physical files and databases is:
A) technology descriptions. B) normalized relations. C) definitions of each attribute.
A rule of thumb for choosing indexes is to:
A) use an index when there is variety in attribute values. B) be careful indexing attributes that may be null. C) index each primary key of each table.
50) What does the following SQL command do? insert into Customer_T values (001,7ohn Smith','231 West StrBoston','MAI;021151);
Adds a new record to the Customer_T
Which of the following is an entity type on which a strong entity depends?
Attribute
In the following diagram, which of the answers below is true?
Both A and C
The normal form which removes any remaining functional dependencies because there was more than one primary key for the same nonkeys is called:
Boyce-Codd normal form.
Which of the following is a component of processing logic?
Business Rules
What is the component of a DBMS that is responsible for storing, retrieving, and updating data?
Database Engine
____ takes a value of true if a subquery returns an intermediate results table which contains one or more rows.
EXISTS
In the following diagram, which answer is true?
Each employee can supervise one to many employees.
In the figure shown below, which of the following business rules would apply?
Each vendor can supply many parts to any number of warehouses, but need not supply any parts
The logical representation of an organization's data is called a(n):
Entity-relationship model
A default value is the value that a field will always assume, regardless of what the user enters for an instance of that field.
F
A join index is a combination of two or more indexes.
F
Denormalization is the process of transforming relations with variable-length fields into those with fixed-length fields.
F
Horizontal partitioning refers to the process of combining several smaller relations into a larger table.
F
The logical database design always forms the best foundation for grouping attributes in the physical design.
F
The smallest unit of named application data is a record.
F
In which type of file is multiple key retrieval not possible?
Hashed
Which type of file is easiest to update?
Hashed
A join that is based upon equality between values in two common columns with the same name and where one duplicate column has been removed is called a(n):
Natural Join
In which data model would a code table appear?
Physical
Which of the following is NOT an advantage of database systems?
Redundant data
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?
Second
Which type of file is most efficient with storage space?
Sequential
The traditional methodology used to develop, maintain and replace information systems is called the:
Systems Development Life Cycle.
A hashing algorithm is a routine that converts a primary key value into a relative record number.
T
A tablespace is a named set of disk storage elements in which physical files for the database tables may be stored.
T
Denormalization almost always leads to more storage space for raw data.
T
Efficient database structures will be beneficial only if queries and the underlying database 45) management system are tuned to properly use the structures.
T
Fast data retrieval is one factor to consider when choosing a file organization for a particular 50) database file.
T
In a sequential file, the records are stored in sequence according to primary key.
T
Keeping the zip code with the city and state in a table is a typical form of denormalization.
T
One decision in the physical design process is selecting structures.
T
Requirements for response time, data security, backup and recovery are all requirements for physical design.
T
In the following diagram, what type of relationship is depicted ?
Ternary
The outer join syntax does not apply easily to a join condition of more than tables.
Two
________ partitioning distributes the columns of a table into several separate physical records.
Vertical
The following figure shows an example of:
a composite attribute.
A user view is:
a logical description of some portion of the database.
40) The SDLC phase in which the detailed conceptual data model is created is the ___ phase.
analysis
An entity type name should be all of the following EXCEPT:
as short as possible.
An entity that associates the instances of one or more entity types and contains attributes specific to the relationships is called a(n):
associative entity
A property or characteristic of an entity type that is of interest to the organization is called a(n):
attribute
A person's name, birthday, and social security number are all examples of:
attributes
A ______ specifies the number of instances of one entity that can be associated with each instance of another entity.
cardinality constraint
An attribute that can be broken down into smaller parts is called a(n) ____ attribute
composite
An attribute that uniquely identifies an entity and consists of a composite attribute is called a(n)
composite identifier
The storage format for each attribute from the logical data model is chosen to maximize ________ and minimize storage space.
data integrity
31) A graphical system used to capture the nature and relationships among data is called a(n):
data model.
Another form of denormalization where the same data are stored in multiple places in the database is called:
data replication
A detailed coding scheme recognized by system software for representing organizational data is called a(n):
data type
A business rule:
defines or constrains some aspect of the business. asserts business structure. controls or influences the behavior of the business.
Designing physical files requires ________ of where and when data are used in various ways.
descriptions
An advantage of partitioning is:
efficiency.
A disadvantage of partitioning is:
extra space and update time.
The smallest unit of application data recognized by system software is a:
field
A(n) ________ is a technique for physically arranging the records of a file on secondary storage devices.
file organization
When all multivalued attributes have been removed from a relation, it is said to be in:
first normal form.
An attribute in a relation of a database that serves as the primary key of another relation in the same database is called a:
foreign key
A constraint between two attributes is called a(n):
functional dependency.
A file organization that uses hashing to map a key into a location in an index where there is a pointer to the actual data record matching the hash key is called a:
hash index table.
A(n) ________ is a routine that converts a primary key value into a relative record number.
hashing algorithm
Distributing the rows of data into separate files is called:
horizontal partitioning.
A(n) _____ is the relationship between a weak entity type and its owner.
identify relationship
The SDLC phase in which database processing programs are created is the ___ phase
implementation
A domain definition consists of the following components EXCEPT:
integrity constraints.
An index on columns from two or more tables that come from the same domain of values is called a:
join index
A rule that states that each foreign key value must match a primary key value in the other relation is called the:
key match rule.
One disadvantage of file processing systems is:
limited data sharing.
A database is an organized collection of _____ related data
logically
A relationship is where the minimum and maximum cardinality are both one is a(n) ____
mandatory one
All of the following are horizontal partitioning methods in Oracle EXCEPT:
multivalued partitioning.
A join in which rows that do not have matching values in common columns are still included in the result table is called a(n): .
outer join
A form of database specification that indicates all the parameters for data storage that are then input to database implementation is:
phyical
An attribute that must have a value for every entity (or relationship) instance is a(n):
required attribute
One field or combination of fields for which more than one record may have the same combination of values is called a(n):
secondary key
The common types of entitites are
strong, associative, weak entities.
A simultaneous relationship among the instances of three entity types is called a(n) ____ relationship
ternary
Database access frequencies are estimated from
transaction volumes.
49) A functional dependency between two or more nonkey attributes is called a:
transitive dependency.
In an E-R diagram, there are ____ business rule(s) for every relationship.
two
The outer join syntax does not apply easily to a join condition of more than ________ tables.
two
Because applications are often developed independently in file processing systems:
unplanned duplicate data files are the rule rather than the exception.
All of the following are objectives when selecting a data type EXCEPT:
use a lot of storage space.
An entity type whose existence depends on another entity type is called a ___ entity.
weak
28) Which of the following types of data can be stored in a database?
A) Voice B) Letters C) Numbers
All of the following are common denormalization opportunities EXCEPT:
a one-to-many relationship.
The SDLC phase in which every data attribute is defined, every category of data is listed and every business relationship between data entities is defined is called the ___ phase.
analysis
A join operation:
causes two tables with a common domain to be combined into a single table or view.
A method to allow adjacent secondary memory space to contain rows from several tables is called:
clustering
A rule that CANNOT be violated by database users is called a:
constraint
In the SQL language, the _____ statement is used to make table definitions.
create table
In most cases the goal of ________ dominates the design process.
efficient data processing
Customers, cars, and parts are examples of
entities
A person, place, an object , an event or concept about which the organization wishes to maintain data is called a(n):
entity