Data-Management-Foundations Exam Dumps : WGU Data Management – Foundations Exam

TheALTER TABLEstatement is used to modify an existing database table structure. One common clause isCHANGE, which allows renaming a column and modifying its data type.

Example:

sql

ALTER TABLE Employees CHANGE COLUMN OldName NewName VARCHAR(50);

Option A (Incorrect):DELETE is used to removerows, not alter table structure.

Option B (Correct):CHANGE is avalid clausefor renaming and modifying columns in MySQL and some other databases.

Option C (Incorrect):STOP is not a valid SQL keyword for altering tables.

Option D (Incorrect):AGGREGATE refers to functions like SUM() and AVG(), not table alterations.

ATransaction ManagerensuresACID (Atomicity, Consistency, Isolation, Durability)properties in database transactions. It manages concurrent transactions, ensuring no conflicts occur and logs modifications to support recovery mechanisms.

Option A (Incorrect):Query optimization is managed by thequery processor, not the transaction manager.

Option B (Incorrect):The transaction manager is a component of the database architecture but is not composed of the entire system (query processor, storage manager, etc.).

Option C (Correct):The transaction manager logs transactions like INSERT, UPDATE, and DELETE, ensuring consistency and recoverability.

Option D (Incorrect):Thestorage manageris responsible for translating queries into filesystem commands.

When performing aJOIN operationin MySQL, the ON clause specifies thejoining condition, defining which columns from both tables should be matched.

Example:

sql

SELECT Employees.Name, Departments.DepartmentName

FROM Employees

JOIN Departments ON Employees.DepartmentID = Departments.ID;

Option A (Incorrect):AS is used foraliasing tables and columns, not for specifying join conditions.

Option B (Incorrect):JOIN defines the type of join (INNER JOIN, LEFT JOIN, etc.), butdoes not specify the columns.

Option C (Correct):The ON clause is used tospecify the join conditionbetween two tables.

Option D (Incorrect):AND is used in filtering conditions, not for joining tables.