WGU Data Management - Foundations Exam Questions

Non-relational databases (also called NoSQL databases) are designed for handling big data and unstructured data efficiently. They are optimized for horizontal scaling, making them ideal for large-scale distributed systems.

Option A (Correct): Non-relational databases are optimized for big data, handling massive volumes of data across distributed architectures.

Option B (Incorrect): NoSQL databases do not use SQL as their primary query language. They often use JSON-based queries (e.g., MongoDB).

Option C (Incorrect): Transaction-heavy applications require ACID compliance, which relational databases (SQL) handle better than NoSQL databases.

Option D (Incorrect): NoSQL databases use document, key-value, graph, or column-family storage models, not tables, columns, and rows like relational databases.

An attribute type refers to a single, specific value within a table, such as Salary, Age, or Price.

Example Usage:

CREATE TABLE Employees (

EmpID INT PRIMARY KEY,

Name VARCHAR(50),

Salary DECIMAL(10,2)

);

Salary is an attribute type with individual values for each employee.

Why Other Options Are Incorrect:

Option A (Glossary) (Incorrect): Refers to documentation, not database values.

Option B (Entity type) (Incorrect): Represents a class of objects (e.g., Employees), not individual values.

Option D (Relationship) (Incorrect): Defines connections between entities, not attributes.

Thus, the correct answer is Attribute type, as it represents an individual data value.

The ABS() function in SQL returns the absolute value of a given number, effectively measuring its distance from zero.

Example Usage:

sql

SELECT ABS(-50), ABS(50);

Result:

50 | 50

This function ensures that numbers are always positive, regardless of their original sign.

Why Other Options Are Incorrect:

Option A (CONCAT) (Incorrect): Used to combine strings (not numbers).

Option B (LOWER) (Incorrect): Converts text to lowercase, not numerical operations.

Option C (FROM) (Incorrect): Part of SELECT FROM queries, not a function.

Thus, the correct choice is ABS(), which computes the absolute value of a number.

In database design, attributes of an entity become columns in a relational table.

Example Usage:

For an Employee entity, attributes might include:

CREATE TABLE Employees (

EmployeeID INT PRIMARY KEY,

Name VARCHAR(50),

Salary DECIMAL(10,2),

DepartmentID INT

);

Each attribute (e.g., Name, Salary) becomes a column in the table.

Why Other Options Are Incorrect:

Option A (Modality) (Incorrect): Describes optional vs. mandatory relationships, not table structure.

Option B (Uniqueness) (Incorrect): Ensures distinct values but is not a column property.

Option D (Non-null values) (Incorrect): Ensures that columns must contain data but does not define attributes.

Thus, the correct answer is Attribute, as attributes of entities become table columns.

In MySQL, the BIGINT data type is a 64-bit integer that requires 8 bytes (64 bits) of storage. It is used to store large numerical values beyond the range of INT (4 bytes).

Option A (Incorrect): 1 byte corresponds to TINYINT, which can store values from -128 to 127.

Option B (Incorrect): 3 bytes is not a standard integer storage size in MySQL.

Option C (Incorrect): 4 bytes corresponds to INT, which has a range of -2,147,483,648 to 2,147,483,647.

Option D (Correct): BIGINT takes 8 bytes and supports a massive range of numbers from -2^63 to 2^63 -1.