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Lam
Lam

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Sql Joins Cheat Sheet

Diagram

SELECT * FROM `A` INNER JOIN `B`
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┌────────┐
│ A  ┌───┼────┐
│    │ ∩ │    │
└────┼───┘  B │
     └────────┘
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Join What
Inner join
Left outer join A +
Right outer join + B
Full outer join A + + B

Example

SELECT * FROM order_items \
  LEFT OUTER JOIN orders \
  ON order_items.order_id = orders.id
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Joins are typically added to SELECT statements to add more columns and records.

Reference

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Socola Đại Ca • Edited

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