WGU D427 OBJECTIVE ASSESSMENT FINAL EXAM AND PRACTICE EXAM NEWEST 2025/2026 ACTUAL EXAM WITH COMPLETE QUESTIONS AND CORRECT DETAILED ANSWERS (100% VERIFIED ANSWERS) |ALREADY GRADED A+| ||PROFESSOR VERIFIED||

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WGU D427 OBJECTIVE ASSESSMENT FINAL EXAM AND PRACTICE
EXAM NEWEST 2025/2026 ACTUAL EXAM WITH COMPLETE
QUESTIONS AND CORRECT DETAILED ANSWERS (100% VERIFIED
ANSWERS) |ALREADY GRADED A+| ||PROFESSOR VERIFIED||

What is the principle of data independence? - ANSWER-The
principle of data independence states that the result of a database
query is not affected by the physical organization of data on
storage devices. This allows database administrators to improve
query performance by changing the organization of data on
storage devices without affecting query results.



How do most databases handle tables with duplicate rows, and
why might they allow duplicates temporarily? - ANSWER-Most
databases allow tables with duplicate rows in violation of the no
duplicate rows rule, but these tables are usually temporary. For
example, external data with duplicate rows might be loaded into a
temporary table, and the duplicate rows are normally eliminated
as data is moved to a permanent table.



Write a SQL statement to create an Employee table with columns
ID (integer), Name (variable-length string with max 60
characters), BirthDate (date), and Salary (decimal with 7 digits

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and 2 decimal places). - ANSWER-CREATE TABLE Employee (
ID INT, Name VARCHAR(60), BirthDate DATE, Salary
DECIMAL(7,2) );



Write a SQL statement to delete the Employee table. - ANSWER-
DROP TABLE Employee;



True or False: The statement `CREATE TABLE Employee (ID INT,
Name VARCHAR(60), BirthDate DATE, Salary DECIMAL(7,2));`
creates an Employee table with 4 columns. - ANSWER-True



True or False: The Name column in the Employee table contains
character string values. - ANSWER-True



True or False: The statement `DROP TABLE Employee;` deletes
the Employee table. - ANSWER-True



True or False: The DROP TABLE statement does not delete the
table unless the table is empty. - ANSWER-False. The table is
deleted regardless of how many rows are in the table.

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Write a SQL statement to create a Product table with columns: ID
(integer), Name (variable-length string with max 40 characters),
ProductType (variable-length string with max 3 characters),
OriginDate (date), and Weight (decimal with 6 significant digits
and 1 digit after the decimal point). - ANSWER-CREATE TABLE
Product ( ID INT, Name VARCHAR(40), ProductType
VARCHAR(3), OriginDate DATE, Weight DECIMAL(6,1) );



What does the ALTER TABLE statement do, and what are the
three main clauses used with it? - ANSWER-The ALTER TABLE
statement adds, deletes, or modifies columns in an existing table.
The three main clauses are: 1. **ADD:** Adds a column. ALTER
TABLE TableName ADD ColumnName DataType; 2.
**CHANGE:** Modifies a column. ALTER TABLE TableName
CHANGE CurrentColumnName NewColumnName NewDataType;
3. **DROP:** Deletes a column. ALTER TABLE TableName
DROP ColumnName;



Write a SQL statement to add a column called Description
(variable-length string with max 50 characters) to the Department

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table. - ANSWER-ALTER TABLE Department ADD Description
VARCHAR(50);



Write a SQL statement to rename the column Description to
ShortDesc in the Department table. - ANSWER-ALTER TABLE
Department CHANGE Description ShortDesc VARCHAR(50);



Write a SQL statement to change the column ShortDesc in the
Department table to accept up to 80 characters. - ANSWER-
ALTER TABLE Department CHANGE ShortDesc ShortDesc
VARCHAR(80);



Write a SQL statement to delete the column ShortDesc from the
Department table. - ANSWER-ALTER TABLE Department DROP
ShortDesc;



What is a data type in relational databases? - ANSWER-A data
type is a named set of values from which column values are
drawn.