SQL Joins

SQL Joins are a way of combining data from two or more tables based on a common column between them. There are four main types of SQL Joins: INNER JOIN, LEFT JOIN, RIGHT JOIN, and FULL JOIN. An INNER JOIN returns only the rows that have matching values in both tables. A LEFT JOIN returns all the rows from the left table and the matched rows from the right table, filling in NULL values for any unmatched rows. A RIGHT JOIN does the opposite, returning all the rows from the right table and the matched rows from the left table. A FULL JOIN returns all the rows from both tables, regardless of whether they have a match or not.

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