Can you explain SQL joins and describe your experience using them?

SQL joins combine rows from two or more tables based on a related column. The main types are:

• INNER JOIN: returns rows with matching keys in both tables.
• LEFT (OUTER) JOIN: returns all rows from the left table and matched rows from the right, filling NULLs when no match.
• RIGHT JOIN: opposite of LEFT.
• FULL (OUTER) JOIN: returns all rows from both tables, NULL where no match.
• CROSS JOIN: Cartesian product of rows.
• SELF JOIN: a table joined to itself.
• NATURAL JOIN: joins on columns with the same name.

I have used INNER and LEFT joins extensively in reporting queries, and I’ve written complex multi‑table joins for data migration scripts. I also use JOINs in ORM queries (e.g., SQLAlchemy) to fetch related objects efficiently.