What is the purpose of using window transactions in SQL and how do they differ from regular transactions?

Window functions in SQL allow performing calculations across a set of table rows that are related to the current row, without grouping the results as in aggregate functions. They operate over a dataset while preserving the original number of rows.

Unlike regular transactions, which manage the atomicity of operations (commit/rollback), window functions are a way to perform analytical processing within a single query.

Example of using a window function:

SELECT employee_id, department_id, salary,
       AVG(salary) OVER (PARTITION BY department_id) AS avg_dept_salary
FROM employees;

Here, the average salary per department is calculated for each row, while all rows remain in the result.

If the question is about transactions in SQL, the term "window transactions" is not standard. It might refer to window functions or managing transactions using window functions for analytics.