WGU D426 A+ Database Applications Objective Assessment Mastery
Guide: Comprehensive Database Systems, Relational Data
Architecture, SQL Programming Fundamentals, Database
Management Concepts, DBMS Components, Database Security
Principles, User Authorization Controls, Query Processing
Optimization, Storage Management Techniques, Transaction
Reliability, Data Modeling Frameworks, Database Design
Methodologies, Entity Relationship Modeling, Logical and Physical
Database Structures, SQL Operations, Data Definition Commands,
Data Types, MySQL Database Administration, API Integration, Data
Independence Concepts, Relational Theory, Tables, Tuples, Columns,
Rows, Database Integrity, Performance Management, Exam-Focused
Concepts, Practice Questions with Detailed Explanations Latest
Reviewed 2026
database application
software that helps business users interact with database systems.
database administrator
responsible for securing the database system against unauthorized users. and enforces
procedures for user access and database system availability.
authorization
Many database users should have limited access to specific tables, columns, or rows of a
database. Database systems authorize individual users to access specific data.
,rules
Database systems ensure data is consistent with structural and business rules
query processor
interprets queries, creates a plan to modify the database or retrieve data, and returns query
results to the application.
query optimization
ensure the most efficient instructions are executed on the data.
storage manager
translates the query processor instructions into low-level file-system commands that modify
or retrieve data. Database sizes range from megabytes to many terabytes, so the storage
manager uses indexes to quickly locate data.
transaction manager
ensures transactions are properly executed. The transaction manager prevents conflicts
between concurrent transactions. The transaction manager also restores the database to a
consistent state in the event of a transaction or system failure.
INSERT
inserts rows into a table
,SELECT
retrieves data from a table
UPDATE
modifies data in a table
DELETE
deletes rows in a table
CREATE TABLE
creates a new table by specifying the table and column names. Each column is assigned a data
type that indicates the format of column values. Data types can be numeric, textual, or
complex.
INT
stores integer values
DECIMAL
Stores fractional numeric values
, VARCHAR
stores textual values
DATE
stores year, month, day
analysis phase
specifies database requirements without regard to a specific database system. Requirements
are represented as entities, relationships, and attributes. An entity is a person, place, activity,
or thing. A relationship is a link between entities, and an attribute is a descriptive property of
an entity. AKA conceptual design, entity-relationship modeling, and requirements definition.
logical design phase
implements database requirements in a specific database system. For relational database
systems, logical design converts entities, relationships, and attributes into tables, keys, and
columns.
physical design
adds indexes and specifies how tables are organized on storage media. Physical design affects
query processing speed but never affects the query result.
Data independence
Guide: Comprehensive Database Systems, Relational Data
Architecture, SQL Programming Fundamentals, Database
Management Concepts, DBMS Components, Database Security
Principles, User Authorization Controls, Query Processing
Optimization, Storage Management Techniques, Transaction
Reliability, Data Modeling Frameworks, Database Design
Methodologies, Entity Relationship Modeling, Logical and Physical
Database Structures, SQL Operations, Data Definition Commands,
Data Types, MySQL Database Administration, API Integration, Data
Independence Concepts, Relational Theory, Tables, Tuples, Columns,
Rows, Database Integrity, Performance Management, Exam-Focused
Concepts, Practice Questions with Detailed Explanations Latest
Reviewed 2026
database application
software that helps business users interact with database systems.
database administrator
responsible for securing the database system against unauthorized users. and enforces
procedures for user access and database system availability.
authorization
Many database users should have limited access to specific tables, columns, or rows of a
database. Database systems authorize individual users to access specific data.
,rules
Database systems ensure data is consistent with structural and business rules
query processor
interprets queries, creates a plan to modify the database or retrieve data, and returns query
results to the application.
query optimization
ensure the most efficient instructions are executed on the data.
storage manager
translates the query processor instructions into low-level file-system commands that modify
or retrieve data. Database sizes range from megabytes to many terabytes, so the storage
manager uses indexes to quickly locate data.
transaction manager
ensures transactions are properly executed. The transaction manager prevents conflicts
between concurrent transactions. The transaction manager also restores the database to a
consistent state in the event of a transaction or system failure.
INSERT
inserts rows into a table
,SELECT
retrieves data from a table
UPDATE
modifies data in a table
DELETE
deletes rows in a table
CREATE TABLE
creates a new table by specifying the table and column names. Each column is assigned a data
type that indicates the format of column values. Data types can be numeric, textual, or
complex.
INT
stores integer values
DECIMAL
Stores fractional numeric values
, VARCHAR
stores textual values
DATE
stores year, month, day
analysis phase
specifies database requirements without regard to a specific database system. Requirements
are represented as entities, relationships, and attributes. An entity is a person, place, activity,
or thing. A relationship is a link between entities, and an attribute is a descriptive property of
an entity. AKA conceptual design, entity-relationship modeling, and requirements definition.
logical design phase
implements database requirements in a specific database system. For relational database
systems, logical design converts entities, relationships, and attributes into tables, keys, and
columns.
physical design
adds indexes and specifies how tables are organized on storage media. Physical design affects
query processing speed but never affects the query result.
Data independence
