Mysql sql查找所有结果的最佳方法显示在两个具有条件的表中

我是sql初学者，希望您能帮助我：

MYSQL服务器5

表1

+----+----------+------------+------+ | ID | USERCODE | ENTITYCODE | DATE | +----+----------+------------+------+ | x | CODE123 | 010011 | ... | | x | CODE123 | 010012 | ... | | x | CODE123 | 010045 | ... | +----+----------+------------+------+ +----+----------+------------+------+ |ID |用户代码|实体代码|日期| +----+----------+------------+------+ |x |代码123 | 010011 || |x |代码123 | 010012 || |x |代码123 | 010045 || +----+----------+------------+------+ 表2

+----+----------+------------+-------------+-------------+ | ID | USERCODE | ENTITYCODE | OTHERFIELD1 | OTHERFIELD2 | +----+----------+------------+-------------+-------------+ | x | CODE123 | 010011 | ... | ... | | x | CODE123 | 010012 | ... | ... | | x | CODE123 | 010045 | ... | ... | | .. | .. | .. | ... | ... | +----+----------+------------+-------------+-------------+ +----+----------+------------+-------------+-------------+ |ID |用户代码|实体代码|其他字段1 |其他字段2| +----+----------+------------+-------------+-------------+ |x |代码123 | 010011 |…|| |x |代码123 | 010012 |……|| |x |代码123 | 010045 |…|| | .. | .. | .. | ... | ... | +----+----------+------------+-------------+-------------+ 实体表

+------------+-------------+-------------+-------------+ | ENTITYCODE | OTHERFIELD1 | OTHERFIELD2 | SPECIALCODE | +------------+-------------+-------------+-------------+ | 010011 | .. | .. | 100 | | 010012 | .. | .. | 105 | | 010045 | .. | .. | 111 | | .. | .. | ... | ... | +------------+-------------+-------------+-------------+ +------------+-------------+-------------+-------------+ |实体代码|其他字段1 |其他字段2 |特殊代码| +------------+-------------+-------------+-------------+ | 010011 | .. | .. | 100 | | 010012 | .. | .. | 105 | | 010045 | .. | .. | 111 | | .. | .. | ... | ... | +------------+-------------+-------------+-------------+ 预期结果

约束：表1、表2和ENTITY.specialcode=105中存在的所有用户代码、实体代码

+-----------+------------+ | USERCODE | ENTITYCODE | +-----------+------------+ | CODE123 | 010012 | +-----------+------------+ +-----------+------------+ |用户代码| ENTITYCODE| +-----------+------------+ |代码123 | 010012| +-----------+------------+ 试一试

参考：

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不起作用，我在结果中得到了重复的行，我不确定distinct是最好的方法…你能用示例datathx创建一个sqlfiddle.com链接吗？很多时候，它工作得很好，我写了相同的请求，但使用了内部连接重复结果

SELECT a.USERCODE , a.ENTITYCODE
FROM table1 a 
JOIN table2 b ON a.USERCODE = b.USERCODE AND a.ENTITYCODE = b.ENTITYCODE
JOIN entity c ON a.ENTITYCODE = c.ENTITYCODE
WHERE c.SPECIALCODE = 105

SELECT USERCODE,ENTITYCODE FROM table1 INNER JOIN table2 ON table1.ENTITYCODE = table2.ENTITYCODE
INNER JOIN entity ON entity.ENTITYCODE = table1.ENTITYCODE
WHERE SPECIALCODE = 105