What is joins? Types of join?

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Accepted Answer

Joins are used to combine rows from two or more tables based on a related column between them.

Types of joins include: INNER JOIN, LEFT JOIN (or LEFT OUTER JOIN), RIGHT JOIN (or RIGHT OUTER JOIN), FULL JOIN (or FULL OUTER JOIN), CROSS JOIN.
INNER JOIN returns rows when there is at least one match in both tables.
LEFT JOIN returns all rows from the left table and the matched rows from the right table.
RIGHT JOIN returns all rows from the right table and the matched rows from the left table.
FULL JOIN returns rows when there is a match in one of the tables.
CROSS JOIN returns the Cartesian product of the two tables.

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