WGU D427 Data Management -
Applications questions fully solved &
updated 2025
database model - answer A database model is a
conceptual framework for database systems, with
three parts:
- Data structures that prescribe how data is
organized.
- Operations that manipulate data structures.
- Rules that govern valid data.
relational model - answer The relational model is
a database model based on a tabular data
structure. The model was published in 1970 by E. F.
Codd of IBM and released in commercial products
around 1980. The data structure, operations, and
rules are standardized in SQL, the universal query
language of relational databases.
big data - answer The rise of the internet in the
1990s generated big data, characterized by
unprecedented data volumes and rapidly changing
data structures.
,set - answer A set is an unordered collection of
elements enclosed in braces.
tuple - answer A tuple is an ordered collection of
elements enclosed in parentheses.
table - answer A table has a name, a fixed tuple of
columns, and a varying set of rows.
column - answer A column has a name and a data
type.
row - answer A row is an unnamed tuple of
values. Each value corresponds to a column and
belongs to the column's data type.
data type - answer A data type is a named set of
values, from which column values are drawn.
relational algebra - answer These operations are
collectively called relational algebra and are the
theoretical foundation of the SQL language.
Relational rules - answer Relational rules are part
of the relational model and govern data in every
relational database.
,Business rules - answer Business rules are based
on business policy and specific to a particular
database.
constraints - answer Relational rules are
implemented as SQL constraints and enforced by
the database system.
Structured Query Language / SQL - answer
Structured Query Language (SQL) is a high-level
computer language for storing, manipulating, and
retrieving data.
statement - answer An SQL statement is a
complete command composed of one or more
clauses.
clause - answer A clause groups SQL keywords
like SELECT, FROM, and WHERE with table names
like City, column names like Name, and conditions
like Population > 100000.
Data Definition Language - answer Data Definition
Language (DDL) defines the structure of the
database.
, Data Query Language - answer Data Query
Language (DQL) retrieves data from the database.
Data Manipulation Language - answer Data
Manipulation Language (DML) manipulates data
stored in a database.
Data Control Language - answer Data Control
Language (DCL) controls database user access.
Data Transaction Language - answer Data
Transaction Language (DTL) manages database
transactions.
database system instance - answer A database
system instance is a single executing copy of a
database system. Personal computers usually run
just one instance of a database system. Shared
computers, such as computers used for cloud
services, usually run multiple instances of a
database system.
CREATE DATABASE DatabaseName - answer
CREATE DATABASE DatabaseName creates a new
database.
Applications questions fully solved &
updated 2025
database model - answer A database model is a
conceptual framework for database systems, with
three parts:
- Data structures that prescribe how data is
organized.
- Operations that manipulate data structures.
- Rules that govern valid data.
relational model - answer The relational model is
a database model based on a tabular data
structure. The model was published in 1970 by E. F.
Codd of IBM and released in commercial products
around 1980. The data structure, operations, and
rules are standardized in SQL, the universal query
language of relational databases.
big data - answer The rise of the internet in the
1990s generated big data, characterized by
unprecedented data volumes and rapidly changing
data structures.
,set - answer A set is an unordered collection of
elements enclosed in braces.
tuple - answer A tuple is an ordered collection of
elements enclosed in parentheses.
table - answer A table has a name, a fixed tuple of
columns, and a varying set of rows.
column - answer A column has a name and a data
type.
row - answer A row is an unnamed tuple of
values. Each value corresponds to a column and
belongs to the column's data type.
data type - answer A data type is a named set of
values, from which column values are drawn.
relational algebra - answer These operations are
collectively called relational algebra and are the
theoretical foundation of the SQL language.
Relational rules - answer Relational rules are part
of the relational model and govern data in every
relational database.
,Business rules - answer Business rules are based
on business policy and specific to a particular
database.
constraints - answer Relational rules are
implemented as SQL constraints and enforced by
the database system.
Structured Query Language / SQL - answer
Structured Query Language (SQL) is a high-level
computer language for storing, manipulating, and
retrieving data.
statement - answer An SQL statement is a
complete command composed of one or more
clauses.
clause - answer A clause groups SQL keywords
like SELECT, FROM, and WHERE with table names
like City, column names like Name, and conditions
like Population > 100000.
Data Definition Language - answer Data Definition
Language (DDL) defines the structure of the
database.
, Data Query Language - answer Data Query
Language (DQL) retrieves data from the database.
Data Manipulation Language - answer Data
Manipulation Language (DML) manipulates data
stored in a database.
Data Control Language - answer Data Control
Language (DCL) controls database user access.
Data Transaction Language - answer Data
Transaction Language (DTL) manages database
transactions.
database system instance - answer A database
system instance is a single executing copy of a
database system. Personal computers usually run
just one instance of a database system. Shared
computers, such as computers used for cloud
services, usually run multiple instances of a
database system.
CREATE DATABASE DatabaseName - answer
CREATE DATABASE DatabaseName creates a new
database.
