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SQL JOIN and different types of JOINs

What is a SQL JOIN and what are different types?

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An illustration from W3schools:


INNER JOIN - Only records which match the condition in both tables


LEFT JOIN - All records from table 1 in conjunction with records which match the condition in table 2


RIGHT JOIN - All records from table 2 in conjunction with records from table 1 which match the condition


FULL OUTER JOIN - Combination of both Left and Right Outer joins matching ON clause but preserving both tables



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