MySQL Equal To Operator

MySQL Equal To Operator

The MySQL = operator is used to compare two values. This operator is essential for filtering records where one value is equal to another.

Syntax

SELECT column1, column2, ...
FROM table_name
WHERE column1 = value;

The = operator has the following components:

  • column1, column2, ...: The columns to be retrieved.
  • table_name: The name of the table from which to retrieve the data.
  • column1 = value: The condition to filter the records, where column1 is equal to a specified value.

Example MySQL Equal To Operator

Let's look at some examples of the MySQL = operator:

Step 1: Using the Database

USE mydatabase;

This query sets the context to the database named mydatabase.

MySQL USE DATABASE

Step 2: Creating a Table

Create a table to work with:

CREATE TABLE employees (
    id INT AUTO_INCREMENT PRIMARY KEY,
    first_name VARCHAR(50) NOT NULL,
    last_name VARCHAR(50) NOT NULL,
    department VARCHAR(50),
    salary DECIMAL(10, 2)
);

This query creates a table named employees with columns for id, first_name, last_name, department, and salary.

MySQL CREATE TABLE

Step 3: Inserting Initial Rows

Insert some initial rows into the table:

INSERT INTO employees (first_name, last_name, department, salary)
VALUES ('John', 'Doe', 'HR', 50000.00),
       ('Jane', 'Smith', 'IT', 60000.00),
       ('Jim', 'Brown', 'IT', 55000.00),
       ('Jake', 'White', 'HR', 52000.00),
       ('Jill', 'Green', 'Marketing', 45000.00);

This query inserts five rows into the employees table.

MySQL INSERT INTO TABLE

Step 4: Using Equal To Operator with WHERE Clause

Use the = operator to filter records based on a condition:

SELECT * 
FROM employees 
WHERE department = 'IT';

This query retrieves all columns from the employees table where the department is equal to 'IT'.

MySQL EQUAL TO WITH WHERE CLAUSE

Step 5: Combining Equal To with AND Operator

Use the = operator with the AND operator to filter records based on multiple conditions:

SELECT * 
FROM employees 
WHERE department = 'HR' AND salary = 52000.00;

This query retrieves all columns from the employees table where the department is 'HR' and the salary is equal to 52000.00.

MySQL EQUAL TO COMBINING WITH AND

Step 6: Using Equal To with Multiple Columns

Use the = operator with multiple columns:

SELECT first_name, last_name 
FROM employees 
WHERE department = 'Marketing' AND salary = 45000.00;

This query retrieves the first_name and last_name columns from the employees table where the department is 'Marketing' and the salary is equal to 45000.00.

MySQL EQUAL TO WITH MULTIPLE COLUMNS

Conclusion

The MySQL = operator is a powerful tool for filtering records based on a comparison condition. Understanding how to use the = operator is essential for effective data querying and analysis in MySQL.