WGU - D426 OBJECTIVE ASSESSMENT
EXAM QUESTIONS AND ANSWERS
Database Model - ANSWER-Data structures that prescribe how data is organized.
Operations that manipulate data structures.
Rules that govern valid data.
Tuple - ANSWER-An ORDERED collection of elements enclosed in parentheses.
Table - ANSWER-A _____ has a name, a fixed tuple of columns, and a varying set
of rows.
Column - ANSWER-A ______ has a name and a data type.
Row - ANSWER-Is an unnamed tuple of values. Each value corresponds to a
column and belongs to the column's data type.
Data Type - ANSWER-A ____ _____ is a named set of values, from which column
values are drawn.
Union - ANSWER-Selects all rows of two tables.
Aggregate - ANSWER-Computes functions over multiple table rows, such as sum
and count.
Relational Rules - ANSWER-Rules that are logical constraints and ensure data is
valid.
The standard language for Relational Databases... - ANSWER-SQL is the standard
language for relational databases, and is commonly supported in non-relational
databases.
Literals (SQL Syntax) - ANSWER-Explicit values that are string, numeric, or
binary.Strings must be surrounded by single quotes or double quotes.Binary values
are represented with x'0' where the 0 is any hex value.
Keywords (SQL Syntax) - ANSWER-Words with special meaning.
ex. SELECT, FROM, WHERE
Identifiers (SQL Syntax) - ANSWER-Objects from the database like tables, columns,
etc.
ex. City, Name, Population
SQL Sublanguages - ANSWER-Data Definition Language (DDL) defines the
structure of the database.
Data Query Language (DQL) retrieves data from the database.
, Data Manipulation Language (DML) manipulates data stored in a database.
Data Control Language (DCL) controls database user access.
Data Transaction Language (DTL) manages database transactions.
Cell - ANSWER-A single column of a single row.
Not Ordered - ANSWER-Rows
Data Independence - ANSWER-Rule 7. Allows database administrators to improve
query performance by changing the organization of data on storage devices, without
affecting query results.
DROP TABLE - ANSWER-Statement that deletes a table, along with all the table's
rows, from a database.
MongoDB (NoSQL) - ANSWER-The newer non-relational systems are called
NoSQL, for 'not only SQL', and are optimized for big data.
SQL Statements - ANSWER-INSERT inserts rows into a table.
SELECT retrieves data from a table.
UPDATE modifies data in a table.
DELETE deletes rows from a table.
CREATE TABLE (Statement) - ANSWER-A statement that 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.
Data Type - ANSWER-INT stores integer values.
DECIMAL stores fractional numeric values.
VARCHAR stores textual values.
DATE stores year, month, and day.
Database Design - ANSWER-Analysis
Logical design
Physical design
Analysis Phase, Conceptual Design, Entity-Relationship Modeling (Database
Design) - ANSWER-This 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.
Logical Design (Database Design) - ANSWER-This phase implements database
requirements in a specific database system. For relational database systems,
_________ design converts entities, relationships, and attributes into tables, keys,
and columns.
EXAM QUESTIONS AND ANSWERS
Database Model - ANSWER-Data structures that prescribe how data is organized.
Operations that manipulate data structures.
Rules that govern valid data.
Tuple - ANSWER-An ORDERED collection of elements enclosed in parentheses.
Table - ANSWER-A _____ has a name, a fixed tuple of columns, and a varying set
of rows.
Column - ANSWER-A ______ has a name and a data type.
Row - ANSWER-Is an unnamed tuple of values. Each value corresponds to a
column and belongs to the column's data type.
Data Type - ANSWER-A ____ _____ is a named set of values, from which column
values are drawn.
Union - ANSWER-Selects all rows of two tables.
Aggregate - ANSWER-Computes functions over multiple table rows, such as sum
and count.
Relational Rules - ANSWER-Rules that are logical constraints and ensure data is
valid.
The standard language for Relational Databases... - ANSWER-SQL is the standard
language for relational databases, and is commonly supported in non-relational
databases.
Literals (SQL Syntax) - ANSWER-Explicit values that are string, numeric, or
binary.Strings must be surrounded by single quotes or double quotes.Binary values
are represented with x'0' where the 0 is any hex value.
Keywords (SQL Syntax) - ANSWER-Words with special meaning.
ex. SELECT, FROM, WHERE
Identifiers (SQL Syntax) - ANSWER-Objects from the database like tables, columns,
etc.
ex. City, Name, Population
SQL Sublanguages - ANSWER-Data Definition Language (DDL) defines the
structure of the database.
Data Query Language (DQL) retrieves data from the database.
, Data Manipulation Language (DML) manipulates data stored in a database.
Data Control Language (DCL) controls database user access.
Data Transaction Language (DTL) manages database transactions.
Cell - ANSWER-A single column of a single row.
Not Ordered - ANSWER-Rows
Data Independence - ANSWER-Rule 7. Allows database administrators to improve
query performance by changing the organization of data on storage devices, without
affecting query results.
DROP TABLE - ANSWER-Statement that deletes a table, along with all the table's
rows, from a database.
MongoDB (NoSQL) - ANSWER-The newer non-relational systems are called
NoSQL, for 'not only SQL', and are optimized for big data.
SQL Statements - ANSWER-INSERT inserts rows into a table.
SELECT retrieves data from a table.
UPDATE modifies data in a table.
DELETE deletes rows from a table.
CREATE TABLE (Statement) - ANSWER-A statement that 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.
Data Type - ANSWER-INT stores integer values.
DECIMAL stores fractional numeric values.
VARCHAR stores textual values.
DATE stores year, month, and day.
Database Design - ANSWER-Analysis
Logical design
Physical design
Analysis Phase, Conceptual Design, Entity-Relationship Modeling (Database
Design) - ANSWER-This 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.
Logical Design (Database Design) - ANSWER-This phase implements database
requirements in a specific database system. For relational database systems,
_________ design converts entities, relationships, and attributes into tables, keys,
and columns.
