本文介绍了将多个子查询转换为 on join的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！
问题描述
我的 sql 中有多个子查询
I have multiple sub-queries in my sql
SELECT *,
(SELECT Col1 FROM MYTABLE2 WHERE SAME) AS Col1,
(SELECT Col2 FROM MYTABLE2 WHERE SAME) AS Col2,
(SELECT Col3 FROM MYTABLE2 WHERE SAME) AS Col3,
(SELECT Col4 FROM MYTABLE2 WHERE SAME) AS Col4,
FROM MYTABLE1 WHERE XXX
如何将其转换为一个 JOIN?子查询相同，只是 Select column-name 不同.
How can I convert this to in one JOIN? Sub Query is same only the Select column-name is different.
推荐答案
SELECT MYTABLE1.*, MYTABLE2.*
FROM MYTABLE1
LEFT OUTER JOIN MYTABLE2
ON same
WHERE XXX
ON 不必关联两个表
这更像是一个过滤的交叉连接
The ON does not have to relate the two tables
This is more like a filtered cross join
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