WGU D427 Data Management – Applications UPDATED ACTUAL Questions
and CORRECT Answers
A database model is a conceptual framework for database
systems, with three parts:
database model - Data structures that prescribe how data is organized.
- Operations that manipulate data structures.
- Rules that govern valid data.
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
relational model
around 1980. The data structure, operations, and rules
are standardized in SQL, the universal query language of
relational databases.
The rise of the internet in the 1990s generated big data,
big data characterized by unprecedented data volumes and rapidly
changing data structures.
A set is an unordered collection of elements enclosed in
set
braces.
A tuple is an ordered collection of elements enclosed in
tuple
parentheses.
A table has a name, a fixed tuple of columns, and a varying
table
set of rows.
column A column has a name and a data type.
A row is an unnamed tuple of values. Each value corre-
row sponds to a column and belongs to the column's data
type.
A data type is a named set of values, from which column
data type
values are drawn.
These operations are collectively called relational algebra
relational algebra
,and are the
theoretical
foundation of
the SQL
language.
, Relational rules are part of the relational model and gov-
Relational rules
ern data in every relational database.
Business rules are based on business policy and specific
Business rules
to a particular database.
Relational rules are implemented as SQL constraints and
constraints
enforced by the database system.
Structured Query Language (SQL) is a high-level comput-
Structured Query Language / SQL
er language for storing, manipulating, and retrieving data.
An SQL statement is a complete command composed of
statement
one or more clauses.
A clause groups SQL keywords like SELECT, FROM, and
clause WHERE with table names like City, column names like
Name, and conditions like Population > 100000.
Data Definition Language (DDL) defines the structure of
Data Definition Language
the database.
Data Query Language (DQL) retrieves data from the data-
Data Query Language
base.
Data Manipulation Language (DML) manipulates data
Data Manipulation Language
stored in a database.
Data Control Language (DCL) controls database user ac-
Data Control Language
cess.
Data Transaction Language (DTL) manages database
Data Transaction Language
transactions.
A database system instance is a single executing copy of a
database system. Personal computers usually run just one
database system instance 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
and CORRECT Answers
A database model is a conceptual framework for database
systems, with three parts:
database model - Data structures that prescribe how data is organized.
- Operations that manipulate data structures.
- Rules that govern valid data.
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
relational model
around 1980. The data structure, operations, and rules
are standardized in SQL, the universal query language of
relational databases.
The rise of the internet in the 1990s generated big data,
big data characterized by unprecedented data volumes and rapidly
changing data structures.
A set is an unordered collection of elements enclosed in
set
braces.
A tuple is an ordered collection of elements enclosed in
tuple
parentheses.
A table has a name, a fixed tuple of columns, and a varying
table
set of rows.
column A column has a name and a data type.
A row is an unnamed tuple of values. Each value corre-
row sponds to a column and belongs to the column's data
type.
A data type is a named set of values, from which column
data type
values are drawn.
These operations are collectively called relational algebra
relational algebra
,and are the
theoretical
foundation of
the SQL
language.
, Relational rules are part of the relational model and gov-
Relational rules
ern data in every relational database.
Business rules are based on business policy and specific
Business rules
to a particular database.
Relational rules are implemented as SQL constraints and
constraints
enforced by the database system.
Structured Query Language (SQL) is a high-level comput-
Structured Query Language / SQL
er language for storing, manipulating, and retrieving data.
An SQL statement is a complete command composed of
statement
one or more clauses.
A clause groups SQL keywords like SELECT, FROM, and
clause WHERE with table names like City, column names like
Name, and conditions like Population > 100000.
Data Definition Language (DDL) defines the structure of
Data Definition Language
the database.
Data Query Language (DQL) retrieves data from the data-
Data Query Language
base.
Data Manipulation Language (DML) manipulates data
Data Manipulation Language
stored in a database.
Data Control Language (DCL) controls database user ac-
Data Control Language
cess.
Data Transaction Language (DTL) manages database
Data Transaction Language
transactions.
A database system instance is a single executing copy of a
database system. Personal computers usually run just one
database system instance 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
