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SQL JOIN 和不同类型的 JOIN

转载 作者:行者123 更新时间:2023-12-04 13:02:59 27 4
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什么是 SQL JOIN什么是不同的类型?

最佳答案

插图来自 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

关于SQL JOIN 和不同类型的 JOIN,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/17946221/

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