SELECT * FROM order_items \ LEFT OUTER JOIN orders \ ON order_items.order_id = orders.id
Joins are typically added to SELECT statements to add more columns and records.
SELECT
SELECT * FROM `A` INNER JOIN `B`
┌────────┐ │ A ┌───┼────┐ │ │ ∩ │ │ └────┼───┘ B │ └────────┘
∩
A
B
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