Wgu_D426_Objective_Assessmentexam_Questions_With_Complete_Solution

WGU - D426: OBJECTIVE ASSESSMENTEXAM QUESTIONS
WITH COMPLETE SOLUTIONS GUARANTEED PASS
2025/2026

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.

ALTER TABLE -ANSWER ->Statement that adds, deletes, or modifies columns on an
existing table.

INT -ANSWER ->4 bytes

, SMALLINT -ANSWER ->2 bytes

BIGINT -ANSWER ->8 bytes

TINYINT -ANSWER ->1 byte

MEDIUMINT -ANSWER ->3 bytes

% (Modulo) -ANSWER ->Divides one numeric value by another and returns the
integer remainder

^ -ANSWER ->Raises one numeric value to the power of another.

= -ANSWER ->Compares two values for equality.

!= -ANSWER ->Compares two values for inequality.

NULL -ANSWER ->A special value that represents either unknown or inapplicable
data.

INSERT Statement (Clauses) -ANSWER ->INTO clause names the table and columns
where data is to be added. The keyword INTO is optional.

VALUES clause specifies the column values to be added.

INSERT Statement (Syntax) -ANSWER ->INSERT [INTO] TableName (Column1,
Column2, ...)VALUES (Value1, Value2, ...);

UPDATE Statement (Clauses) -ANSWER ->Uses the SET clause to specify the new
column values.
An optional WHERE clause specifies which rows are updated.
Omitting the WHERE clause results in all rows being updated.