Quizzes Flashcards
T or F: Data and information are essentially the same thing.
False
T or F: Data constitute the building blocks of information.
True
T or F: Metadata describe the data characteristics and the set of relationships that links the data found within the database.
True
T or F: One disadvantage of the DBMS is that it increases the risk of data security breaches.
False
T or F: Corporations use only structured data.
False
T or F: Field refers to a collection of related records.
False
T or F: Data is the result of processing raw facts to reveal its meaning.
False
T or F: Database programming languages receive all application requests and translate them into the complex operations required to fulfill those requests.
False
T or F: The DBMS reveals much of the database’s internal complexity to the application programs and users.
False
T or F: One disadvantage of a database system over previous data management approaches is increased costs.
True
T or F: In the context of data models, an entity is a person, place, thing, or event about which data will be collected and stored.
True
T or F: Business rules apply to businesses and government groups, but not to other types of organizations such as religious groups or research laboratories.
False
T or F: Business rules must be rendered in writing.
True
T or F: Each row in the relational table is known as an entity instance or entity occurrence in the ER model.
True
Which of the following is true of business rules?
They can be a communication tool between the users & designers.
They allow the designer to develop business processes.
They allow the designer to set company policies with regard to data.
They provide a framework for the company’s self-actualization.
They can be a communication tool between the users & designers.
A noun in a business rule translates to a(n) _____ in the data model.
relationship
entity
attribute
constraint
entity
A verb associating two nouns in a business rule translates to a(n) _____ in the data model.
constraint
relationship
attribute
entity
relationship
MySQL is an example of the _____.
XML data model
file system data model
hierarchical model
relational data model
relational data model
T or F: M:N relationships are not appropriate in a relational model.
True
Which of the following is true of NoSQL databases?
They are not based on the relational model.
They do not support distributed database architectures.
They do not support very large amounts of sparse data.
They are geared toward transaction consistency rather than
performance.
They are not based on the relational model.
T or F: All SQL commands must be issued on a single line.
False
T or F: Although SQL commands can be grouped together on a single line, complex command sequences are best shown on separate lines, with space between the SQL command and the command’s components.
True
T or F: Comparison operators cannot be used to place restrictions on character-based attributes.
False
T or F: String comparisons are made from left to right.
True
T or F: Most SQL implementations yield case-insensitive searches.
True
The SQL command that allows a user to permanently save data changes is _____.
COMMIT
UPDATE
INSERT
SELECT
COMMIT
How many rows would be returned from a cross join of tables A and B, if A contains 8 rows and B contains 18?
8
144
26
18
144
The SQL aggregate function that gives the number of rows containing non-null values for a given column is _____.
COUNT
MIN
MAX
SUM
COUNT
T or F: SQL is considered difficult to learn; its command set has a vocabulary of more than 300 words.
False
A(n) _____ is a query that is embedded (or nested) inside another query.
view
alias
operator
subquery
subquery
T or F: The practical significance of taking the logical view of a database is that it serves as a reminder of the simple file concept of data storage.
True
T or F: The order of the rows and columns is important to the DBMS.
False
T or F: Only a single attribute, not multiple attributes, can define functional dependence.
False
T or F: RDBMSs enforce integrity rules automatically.
True
T or F: Relational algebra defines the theoretical way of manipulating table contents using relational operators.
True
T or F: The SELECT operator yields a vertical subset of a table.
False
T or F: In a natural join, the column on which the join was made occurs twice in the new table.
False
T or F: 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.
False
Referential _____ dictates that the foreign key must contain values that match the primary key in the related table, or must contain null.
model
integrity
uniqueness
attribute
integrity
_____ relationships can be implemented by creating a new entity in 1:M relationships with the original entities.
M:N
1:N
M:1
1:1
M:N
T or F: The entity relationship model (ERM) is dependent on the database type.
False
T or F: In the entity relationship model, a table row corresponds to an entity instance.
True
T or F: Relationships between entities always operate in one direction.
False
T or F: Referential integrity and participation are both bidirectional, meaning that they must be addressed in both directions along a relationship.
False
When the specific cardinalities are not included on the diagram in Crow’s Foot notation, cardinality is implied by the use of _____.
symbols
attributes
images
tables
symbols
The existence of a(n) _____ entity indicates that its minimum cardinality is zero.
ternary
optional
strong
weak
optional
The entity relationship model uses the associative entity to represent a(n) _____ relationship between two or more entities.
M:N
1:M
N:1
M:1
M:N
The first step in building an entity-relationship diagram (ERD) is _____.
developing the initial ERD
creating a detailed narrative of the organization’s description of
operations
identifying the attributes and primary keys that adequately describe
the entities
identifying the business rules based on the description of
operations
creating a detailed narrative of the organization’s description of operations
In organizations that generate large number of transactions, _____ are often a top priority in database design.
relationships among entities
logical design standards
naming conventions
high processing speeds
high processing speeds
Database design is a(n) _____ process based on repetition.
sequential
iterative
linear
intermittent
iterative
T or F: Normalization works through a series of stages called normal forms.
True
T or F: Normalization is a process that is used for changing attributes to entities.
False
T or F: Denormalization produces a lower normal form.
True
T or F: Relational models view data as part of a table or collection of tables in which all key values must be identified.
True
T or F: All relational tables satisfy the 1NF requirements.
True
T or F: It is possible for a table in 2NF to exhibit transitive dependency, where the primary key may rely on one or more nonprime attributes to functionally determine other nonprime attributes.
True
From a structural point of view, 3NF is better than _____.
5NF
3NF
2NF
6NF
2NF
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 _____.
2NF
3NF
4NF
1NF
1NF
Dependencies based on only a part of a composite primary key are known as _____ dependencies.
partial
primary
composite
incomplete
partial
A table where all attributes are dependent on the primary key but are independent of each other, and no row contains two or more multivalued facts about an entity is said to be in _____.
3NF
1NF
2NF
4NF
4NF
ome very specialized applications may require normalization beyond the _____.
1NF
4NF
2NF
3NF
4NF
A relational table must not contain a(n) _____.
attribute
entity
relationship
repeating group
repeating group
A table that is in 2NF and contains no transitive dependencies is said to be in _____.
2NF
4NF
1NF
3NF
3NF
An atomic attribute _____.
displays multiplicity
is always chosen to be a foreign key
cannot be further subdivided
cannot exist in a relational table
cannot be further subdivided
T or F: In order to meet performance requirements, portions of the database design may need to be occasionally denormalized.
True
T or F: Relational models view data as part of a table or collection of tables in which all key values must be identified.
True
T or F: A dependency of one nonprime attribute on another nonprime attribute is a partial dependency.
False
T or F: In the context of partial dependencies, data redundancies occur because every row entry requires duplication of data.
True
T or F: A table is in BCNF if every determinant in the table is a foreign key.
False
T or F: The combination of normalization and ER modeling yields a useful ERD, whose entities can be translated into appropriate table structures.
True
T or F: A view is a virtual table based on a SELECT query.
True
T or F: A persistent stored module is stored and executed on the database client machine.
False
T or F: A trigger is procedural SQL code that is automatically invoked by the RDBMS upon the occurrence of a given data manipulation event.
True
T or F: Triggers can only be used to update table values.
False
T or F: MySQL allows multiple triggering conditions per trigger.
False
T or F: Just like database triggers, stored procedures are stored in the database.
True
T or F: An explicit cursor must return two or more rows.
False
When writing SQL table-creating command sequences, the entire table definition is enclosed in _____.
asterisks
quotations
commas
parentheses
parentheses
T or F: Every PL/SQL block must be given a name.
False
The CREATE TABLE command lets you define constraints when you use the CONSTRAINT keyword, known as a(n) _____ constraint.
index
column
table
cell
table
T or F: Systems analysis establishes the need for an information system and its extent.
True
T or F: The primary objective in database design is to create complete, normalized, nonredundant, and fully integrated conceptual, logical, and physical database models.
True
T or F: In the detailed systems design phase of the Systems Development Life Cycle (SDLC), steps are laid out for the conversion of a database from an old system to a new system.
True
T or F: The database contents might be loaded interactively or in batch mode using a variety of methods and devices including customized user programs.
True
T or F: A system maintenance activity generated in response to changes in the business environment is referred to as corrective maintenance.
False
T or F: The overall purpose of the database initial study is to create the conceptual design.
False
T or F: Data integrity is enforced by the database management system (DBMS) through the proper use of primary and foreign key rules.
True
Coding, testing, and debugging are part of the _____ phase of the Systems Development Life Cycle (SDLC).
analysis
detailed systems design
implementation
planning
implementation
“Should the existing system be replaced?” is a question that is asked during the _____ stage of the Systems Development Life Cycle (SDLC).
analysis
implementation
maintenance
planning
planning
T or F: The testing and evaluation phase of the Database Life Cycle (DBLC) occurs after applications programming.
False
T or F: Most real-world database transactions are formed by only one database request.
False
T or F: The DBMS guarantees that the semantic meaning of a transaction truly represents the real-world event.
False
T or F: The multiuser DBMS must implement controls to ensure serializability and isolation of transactions, in addition to atomicity and durability, in order to guard the database’s consistency and integrity.
True
T or F: The phenomenon of uncommitted data occurs when two transactions are executed concurrently and the first transaction is rolled back after the second transaction has already accessed the uncommitted data—thus violating the isolation property of transactions.
True
T or F: A scheduler facilitates data isolation to ensure that two transactions do not update the same data element at the same time.
True
T or F: In a page-level lock, the DBMS will lock an entire diskpage.
True
T or F: A field-level lock allows concurrent transactions to access the same row, as long as they require the use of different fields within that row.
True
T or F: A growing phase in a two-phase lock is when a transaction acquires all the required locks without locking any data.
False
T or F: An optimistic approach is based on the assumption that the majority of the database operations do not conflict.
True
ANSI has defined standards that govern SQL database transactions. Transaction support is provided by two SQL statements _____ and ROLLBACK.
RETRIEVE
ASSIGN
COMMIT
UPDATE
COMMIT
T or F: One of the main functions of a database system is to provide timely answers to end users.
True
T or F: Good database performance is easy to evaluate.
False
T or F: The SQL cache stores the end-user written SQL.
False
T or F: The purpose of an I/O operation is to move data to and from different computer components or devices.
True
T or F: Working with data in the data cache is many times faster than working with data in the data files.
True
T or F: Fully equivalent means that the optimized query results are always the same as the original query.
True
T or F: The SQL execution activities are performed by the query optimizer.
False
T or F: An index scan is less efficient than a full table scan.
False
T or F: Indexes do not facilitate join operations.
False
T or F: RAID systems use a single disk to create storage volumes.
False
T or F: A distributed database management system (DDBMS) governs the storage and processing of logically related data over interconnected computer systems.
True
T or F: The web is the repository for distributed data.
True
T or F: Current distributed database management system (DDBMS) are subject to some problems, such as the complexity of management and control.
True
T or F: One of the advantages of a distributed database management system (DDBMS) is that the data is located near the site with the least demand.
False
T or F: In order to manage distributed data, copies or parts of the database processing functions must be distributed to all data storage sites.
True
T or F: A fully distributed database management system (DBMS) must perform all the functions of a centralized DBMS, and it must handle all necessary functions imposed by the distribution of data and processing.
True
T or F: The transaction processor (TP) is the software component found in each computer that requests data.
True
T or F: Distributed data access was needed to support geographically dispersed business units.
True
T or F: A distributed database management system (DDBMS) must be communications-media-dependent.
False
T or F: Distributed database systems do not require complex mechanisms to manage transactions and ensure the database’s consistency and integrity.
False
T or F: Business intelligence (BI) architecture is composed of data, people, processes, and technology working together to facilitate and enhance a business’s management and governance.
True
T or F: Master data management’s main goal is to provide a partial and segmented definition of all data within an organization.
False
T or F: Decision support data is a snapshot of the operational data at a given point in time.
True
T or F: Normalizing fact tables improves data access performance and saves data storage space.
False
T or F: Advanced OLAP feature become more useful when access to them is kept simple.
True
From a data analyst’s point of view, decision support data differ from operational data in three main areas: time span, granularity, and _____.
dimensionality
transaction processing
sparsity
usability
dimensionality
Operational data are commonly stored in many tables, and the stored data represents information about a given _____ only.
transaction
table
concept
database
transaction
In a star schema, attributes are often used to search, filter, or classify _____.
facts
sales
dimensions
tables
facts
T or F: Operational data and decision support data serve the same purpose.
False
In business intelligence framework, data are captured from a production system and placed in _____ on a near real-time basis.
portal
dashboard
decision support system
data warehouse
data warehouse
T or F: Scaling out is keeping the same number of systems, but migrating each system to a larger one.
False
T or F: In many ways, the issues associated with volume and velocity are the same.
True
T or F: Relational databases rely on unstructured data.
False
T or F: Big Data processing imposes a structure on the data as needed for applications as a part of retrieval and processing.
True
T or F: The ability to graphically present data in a way that makes it understandable is the concept of value.
False
T or F: A column family database is a NoSQL database model that organizes data in key-value pairs with keys mapped to a set of columns in the value component.
True
Which of the following is NOT one of the standard NoSQL categories?
Column-oriented databases
Chart databases
Graph databases
Document databases
Chart databases
Graph theory is a mathematical and computer science field that models relationships, or edges, between objects called ______.
nodes
scales
maps
buckets
nodes
Document databases group documents into logical groups called ______.
collections
blocks
buckets
sets
collections
Data collected or aggregated around a central topic or entity is said to be ______ aware.
feedback
aggregate
visually
transversally
aggregate