如何修复查询条件或其他任何内容

Posted 2023-04-19

【中文标题】如何修复查询条件或其他任何内容

【英文标题】：How to fix query where condition or anything else

【发布时间】：2019-01-08 05:39:22

【问题描述】：

预期的输出是传递的数据 但是在运行查询时，即使断开连接也无法正常工作 它发生在添加'和pass_fail like 'pass''这个条件时

我使用的是 mysql 工作台 8.0

select A.serial_no
     , A.test01  
     , C.test02
     , D.test03
     , E.test04 
     , F.test05
     , G.test06
     , H.test07
     , I.test08
     , J.test09
     , K.test10
from 
(    select  serial_no
            , test01
        from AA 
        where serial_no >= '%s' 
          and serial_no <= '%s' 
          and pass_fail like 'pass'
          and register_date IN ( select  max(register_date) as date
                                                    from AA 
                                                    where serial_no >= '%s' 
                                                      and serial_no <= '%s' 
                                                    group by serial_no )                              
) A
,(   
      select  serial_no
            , test02                  
              from BB 
              where serial_no >= '%s' 
                and serial_no <= '%s' 
                and pass_fail like 'pass'
                and register_date IN ( select  max(register_date) as date
                                                            from BB 
                                                            where serial_no >= '%s' 
                                                              and serial_no <= '%s' 
                                                            group by serial_no)
 )B
,(
      select   serial_no
            ,  test03
              from CC
              where serial_no >= '%s' 
                and serial_no <= '%s' 
                and pass_fail like 'pass'  
                and register_date IN ( select  max(register_date) as date
                                                            from CC 
                                                            where serial_no >= '%s' 
                                                              and serial_no <= '%s' 
                                                            group by serial_no)
)D
,(
      select  serial_no
             , test04            
        from DD
        where serial_no >= '%s' 
          and serial_no <= '%s' 
          and pass_fail like 'pass'  
          and register_date IN ( select  max(register_date) as date
                                                            from DD 
                                                            where serial_no >= '%s' 
                                                              and serial_no <= '%s' 
                                                            group by serial_no)
)E
,(
      select  serial_no
            , test05                       
        from EE
        where serial_no >= '%s' 
          and serial_no <= '%s' 
          and pass_fail like 'pass'  
          and register_date IN ( select  max(register_date) as date
                                                            from EE 
                                                            where serial_no >= '%s' 
                                                              and serial_no <= '%s' 
                                                            group by serial_no)
)F
,(
      select serial_no
            , test06                       
        from FF
        where serial_no >= '%s' 
          and serial_no <= '%s' 
          and pass_fail like 'pass'  
          and register_date IN ( select  max(register_date) as date
                                                            from FF 
                                                            where serial_no >= '%s' 
                                                              and serial_no <= '%s' 
                                                            group by serial_no)
)G
,(
      select  serial_no
            , test07  
        from GG
        where serial_no >= '%s' 
          and serial_no <= '%s' 
          and pass_fail like 'pass'  
          and register_date IN ( select  max(register_date) as date
                                                            from GG 
                                                            where serial_no >= '%s' 
                                                              and serial_no <= '%s' )
)H
,(
      select  serial_no
            ,  test08
        from HH
        where serial_no >= '%s' 
          and serial_no <= '%s' 
          and pass_fail like 'pass'  
          and register_date IN ( select  max(register_date) as date
                                                            from HH 
                                                            where serial_no >= '%s' 
                                                              and serial_no <= '%s' )
)I
,(
      select   serial_no
            ,  test09
        from II
        where serial_no >= '%s' 
          and serial_no <= '%s' 
          and pass_fail like 'pass'  
          and register_date IN ( select  max(register_date) as date
                                                            from II 
                                                            where serial_no >= '%s' 
                                                              and serial_no <= '%s' )
)J
,(
      select  serial_no
          ,  test10
        from JJ
        where serial_no >= '%s' 
          and serial_no <= '%s' 
          and pass_fail like 'pass'  
          and register_date IN ( select  max(register_date) as date
                                                            from JJ 
                                                            where serial_no >= '%s' 
                                                              and serial_no <= '%s' )
)K
where A.serial_no = C.serial_no    
and C.serial_no = D.serial_no 
and D.serial_no = E.serial_no 
and E.serial_no = F.serial_no    
and F.serial_no = G.serial_no    
and G.serial_no = H.serial_no    
and H.serial_no = I.serial_no    
and I.serial_no = J.serial_no    
and J.serial_no = K.serial_no

预期结果：传递的数据 实际结果：失去连接

它不能使用解释查询 https://dev.mysql.com/doc/refman/8.0/en/explain.html

【参考方案1】：

如果您使用 IN 子句和子查询，则不要为子查询列使用别名 请记住，在 IN 子句中可用的结果是有限的（这两个原因应该是您错误的主要候选人）

  and register_date IN ( select  max(register_date) 
                    from DD 
                    where serial_no >= '%s' 
                      and serial_no <= '%s' 
                    group by serial_no)

为了避免 IN 限制以获得更好的性能，您可以使用内部联接而不是 IN 子句 a 重构查询

所以

select A.serial_no
     , A.test01 
     ....... 
from 
(    select  serial_no
            , test01
    from AA 
    INNER JOIN (
      select serial_no, max(register_date) as date
      from AA 
      where serial_no = '%s' 
      group by serial_no 
    ) X ON X.serial_no = AA.serial_no AND X.date = AA.register_date
        where pass_fail like 'pass'
) A  

........

看看for where条件

where serial_no >= '%s' 
and serial_no <= '%s'  

等于

where serial_no = '%s' 

...

你不应该使用旧的基于逗号分隔的隐式连接sintax和where条件，而是使用显式连接sintax

FROM A 
INNER JOIN (

.....

) C ON A.serial_no = C.serial_no
...