Question

我有

SELECT clientReport.id 
FROM clientReport 
LEFT JOIN report02 ON (report02.id = clientReport.id)
WHERE report02.id is null;

相当于

SELECT clientReport.id
WHERE clientReport.rowNumber NOT EXISTS (
SELECT clientReport.rowNumber FROM report02, clientReport
WHERE report02.id=clientReport.id);

我可能需要一个完整的内部联接来获取report02中的不匹配，而不仅仅是clientReport。如何编写联接来执行此操作？

Answer 1

以下内容应该有效。

SELECT clientReport.id,report02.id
FROM clientReport 
FULL OUTER JOIN report02 ON (report02.id = clientReport.id)
WHERE report02.id is null
OR clientReport.id is null;

应该但它没有（因为MySQL目前不支持FULL OUTER JOIN。）

这更有可能奏效：

( SELECT clientReport.id  AS report01
       , report02.id      AS report02
  FROM clientReport 
  LEFT  OUTER JOIN report02
      ON (report02.id = clientReport.id)
  WHERE report02.id IS NULL
)
UNION
( SELECT clientReport.id  AS report01
       , report02.id      AS report02
  FROM clientReport 
  RIGHT OUTER JOIN report02
      ON (report02.id = clientReport.id)
  WHERE clientReport.id is null
)

MySQL全内连接

1 个答案: