JOIN database statement

The JOIN statement in SQL is used to combine data from multiple tables based on a related column, typically using primary keys and foreign keys. This allows retrieving meaningful data across different tables.

Choosing the Right JOIN

INNER JOIN → Use when you only need matching records.

LEFT JOIN → Use when you want all records from the first table, even if there's no match.

RIGHT JOIN → Use when you need all records from the second table, even if there's no match.

FULL JOIN → Use when you need all records from both tables.

SELF JOIN → Use for comparing records within the same table.

CROSS JOIN → Use when you need all possible row combinations.


INNER JOIN is a default JOIN type, when keyword INNER is omitted.

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