Is it possible to implement business logic using SQL queries?

Yes, to some extent, programmatic logic can be implemented using SQL queries, especially by utilizing advanced database features such as:

• Stored procedures and functions
• Triggers
• Conditional operators (CASE)
• Loops and control structures in procedural SQL extensions (e.g., PL/pgSQL, T-SQL)

This allows performing calculations, checking conditions, updating data, and even implementing complex business rules directly at the database level.

Example of a simple condition in SQL:

SELECT 
  employee_id, 
  salary,
  CASE 
    WHEN salary > 5000 THEN 'High'
    ELSE 'Low'
  END AS salary_level
FROM employees;

However, it is important to remember that complex business logic is usually better implemented in the application, with SQL used for data manipulation. Excessive use of logic in SQL can lead to complex and hard-to-maintain code.