1. INSERT Statement:

The INSERT statement is used to add new records (rows) to a table in a database.

Variation 1: Inserting a Single Record

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INSERT INTO employees (employee_id, employee_name, department_id, salary)
VALUES (101, 'John Doe', 1, 55000);

• In this example, we're inserting a single record into the employees table.
• We specify the columns we're inserting data into and provide the corresponding values.

Variation 2: Inserting Multiple Records

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INSERT INTO employees (employee_id, employee_name, department_id, salary)
VALUES
  (102, 'Jane Smith', 2, 60000),
  (103, 'Bob Johnson', 1, 58000);

• Here, we're inserting multiple records into the employees table in a single INSERT statement.
• Each set of values in parentheses represents a new record.

2. UPDATE Statement:

The UPDATE statement is used to modify existing records in a table.

Variation 1: Updating a Single Record

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UPDATE employees
SET salary = 62000
WHERE employee_id = 102;

• In this example, we're updating the salary of a single employee with employee_id equal to 102 in the employees table.

Variation 2: Updating Multiple Records

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UPDATE employees
SET department_id = 3
WHERE department_id = 1;

• Here, we're updating the department_id for multiple employees in the employees table.
• The WHERE clause specifies the condition for selecting the records to be updated.

3. DELETE Statement: