oracle 关联子查询

Others 2021-12-10 10:04:10 views: null

关联子查询：

什么是关联子查询？

内查询的执行需要借助外查询，而外查询的执行又离不开内查询的执行，这时，内查询和外查询是相互关联的，这种子查询就被称为关联子查询。

在关联子查询中，内查询能够引用外部查询的列，对外部查询的每一行，内部查询都要执行一次。

关联子查询举例：

看一个例子&

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Origin blog.csdn.net/qq_45696288/article/details/121253151
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