Question

每个人我都有问题。我有两个查询，运行良好分开。但是我想在我尝试的一个查询中进行，但那些不起作用。我需要加入两个输出。

首先查询：

SELECT q_internal_table.q_part_id, 
   q_external_table.q_external_id, 
   q_external_table.q_external_approve, 
   q_external_table.q_order_id, 
   q_internal_table.q_internal_id, 
   q_internal_table.q_internal_approve 
   FROM   (SELECT parts.id                  AS q_part_id, 
           parts.order_id            AS q_order_id, 
           external_reports.id       AS q_external_id, 
           external_reports.approved AS q_external_approve 
    FROM   parts 
           INNER JOIN external_reports 
                   ON( parts.id = external_reports.part_id )) 
   q_external_table 
   INNER JOIN (SELECT parts.id                  AS q_part_id, 
                      internal_reports.id       AS q_internal_id, 
                      internal_reports.approved AS q_internal_approve 
               FROM   parts 
                      INNER JOIN internal_reports 
                              ON( parts.id = internal_reports.part_id )) 
          q_internal_table 
           ON( q_external_table.q_part_id = q_internal_table.q_part_id ) 
   WHERE  ( q_external_table.q_external_approve = 'Y' 
      OR q_internal_table.q_internal_approve = 'Y' )

第二次查询：

SELECT q_five_internal_table.q_five_part_id,
   q_five_internal_table.q_five_internal_id, 
   q_five_internal_table.q_five_internal_approve,
   q_five_external_table.q_five_external_id, 
   q_five_external_table.q_five_external_approve, 
   q_five_external_table.q_five_order_id
   FROM   (SELECT parts.id                  AS q_five_part_id, 
           parts.order_id            AS q_five_order_id, 
           five_way_external_reports.id       AS q_five_external_id, 
           five_way_external_reports.approved AS q_five_external_approve 
    FROM   parts 
           INNER JOIN five_way_external_reports 
                   ON( parts.id = five_way_external_reports.part_id )) 
   q_five_external_table 
   INNER JOIN (SELECT parts.id                  AS q_five_part_id, 
                      five_way_internal_reports.id       AS q_five_internal_id, 
                      five_way_internal_reports.approved AS q_five_internal_approve 
               FROM   parts 
                      INNER JOIN five_way_internal_reports 
                              ON( parts.id = five_way_internal_reports.part_id )) 
          q_five_internal_table 
           ON( q_five_external_table.q_five_part_id = q_five_internal_table.q_five_part_id ) 
  WHERE  ( q_five_external_table.q_five_external_approve = 'Y' 
      OR q_five_internal_table.q_five_internal_approve = 'Y' )

首先查询结果：

第二个查询结果：

我试过了这个问题： -

SELECT q_internal_external_table.*, 
   q_five_internal_external_table.* 
FROM   (SELECT q_internal_table.q_part_id, 
           q_external_table.q_external_id, 
           q_external_table.q_external_approve, 
           q_external_table.q_order_id, 
           q_internal_table.q_internal_id, 
           q_internal_table.q_internal_approve 
    FROM  (SELECT parts.id                  AS q_part_id, 
                  parts.order_id            AS q_order_id, 
                  external_reports.id       AS q_external_id, 
                  external_reports.approved AS q_external_approve 
           FROM   parts 
                  INNER JOIN external_reports 
                          ON( parts.id = external_reports.part_id )) 
          q_external_table 
          INNER JOIN (SELECT parts.id                  AS q_part_id, 
                             internal_reports.id       AS q_internal_id, 
                             internal_reports.approved AS q_internal_approve 
                      FROM   parts 
                             INNER JOIN internal_reports 
        ON( parts.id = internal_reports.part_id )) 
        q_internal_table 
       ON( q_external_table.q_part_id = q_internal_table.q_part_id ) 
       WHERE  ( q_external_table.q_external_approve = 'Y' 
       OR q_internal_table.q_internal_approve = 'Y' )) 
       q_internal_external_table 
       INNER JOIN (SELECT q_five_internal_table.q_five_part_id, 
       q_five_internal_table.q_five_internal_id, 
       q_five_internal_table.q_five_internal_approve, 
       q_five_external_table.q_five_order_id, 
       q_five_external_table.q_five_external_id, 
       q_five_external_table.q_five_external_approve 
       FROM   (SELECT parts.id                           AS q_five_part_id, 
       parts.order_id                     AS 
       q_five_order_id 
       , 
      five_way_external_reports.id       AS 
       q_five_external_id, 
       five_way_external_reports.approved AS 
       q_five_external_approve 
       FROM   parts 
       INNER JOIN five_way_external_reports 
       ON( parts.id = five_way_external_reports.part_id )) 
       q_five_external_table 
       INNER JOIN (SELECT parts.id  AS     q_five_part_id, 
       five_way_internal_reports.id       AS 
       q_five_internal_id, 
       five_way_internal_reports.approved AS 
       q_five_internal_approve 
       FROM   parts 
       INNER JOIN five_way_internal_reports 
       ON( parts.id = five_way_internal_reports.part_id )) 
       q_five_internal_table 
       ON ( q_five_external_table.q_five_part_id = 
       q_five_internal_table.q_five_part_id ) 
       WHERE  ( q_five_external_table.q_five_external_approve = 'Y' 
       OR q_five_internal_table.q_five_internal_approve = 'Y' )) 
       q_five_internal_external_table 
       ON ( q_internal_external_table.q_part_id = 
       q_five_internal_external_table.q_five_part_id )

QUERY结果： - 在此查询中有三个结果。但我想在第一个查询结果中得到7结果。这三个答案已经在第一个查询结果中。我也需要休息4。我认为问题出在ON q_internal_external_table.q_part_id = q_five_internal_external_table.q_five_part_id。但不知道如何解决它。

请帮帮我。提前谢谢。

Answer 1

您需要的是UNION。

两个查询都需要具有相同数量的列和类型。在您的情况下，您需要更改所选列的顺序，以便生成UNION。

应该是这样的：

SELECT q_internal_table.q_part_id, 
   q_external_table.q_external_id, 
   q_external_table.q_external_approve, 
   q_external_table.q_order_id, 
   q_internal_table.q_internal_id, 
   q_internal_table.q_internal_approve 
   FROM   (SELECT parts.id AS q_part_id, 
           parts.order_id AS q_order_id, 
           external_reports.id AS q_external_id, 
           external_reports.approved AS q_external_approve 
    FROM parts 
           INNER JOIN external_reports 
                   ON( parts.id = external_reports.part_id )) 
   q_external_table 
   INNER JOIN (SELECT parts.id AS q_part_id, 
                      internal_reports.id AS q_internal_id, 
                      internal_reports.approved AS q_internal_approve 
               FROM   parts 
                      INNER JOIN internal_reports 
                              ON( parts.id = internal_reports.part_id )) 
          q_internal_table 
           ON( q_external_table.q_part_id = q_internal_table.q_part_id ) 
   WHERE  ( q_external_table.q_external_approve = 'Y' 
      OR q_internal_table.q_internal_approve = 'Y' )

UNION ALL 

SELECT q_five_internal_table.q_five_part_id,
      q_five_external_table.q_five_external_id,
      q_five_external_table.q_five_external_approve, 
      q_five_external_table.q_five_order_id,
   q_five_internal_table.q_five_internal_id, 
   q_five_internal_table.q_five_internal_approve   
   FROM   (SELECT parts.id AS q_five_part_id, 
           parts.order_id AS q_five_order_id, 
           five_way_external_reports.id AS q_five_external_id, 
           five_way_external_reports.approved AS q_five_external_approve 
    FROM   parts 
           INNER JOIN five_way_external_reports 
                   ON( parts.id = five_way_external_reports.part_id )) 
   q_five_external_table 
   INNER JOIN (SELECT parts.id AS q_five_part_id, 
                      five_way_internal_reports.id AS q_five_internal_id, 
                      five_way_internal_reports.approved AS q_five_internal_approve 
               FROM parts 
                      INNER JOIN five_way_internal_reports 
                              ON( parts.id = five_way_internal_reports.part_id )) 
          q_five_internal_table 
           ON( q_five_external_table.q_five_part_id = q_five_internal_table.q_five_part_id ) 
  WHERE  ( q_five_external_table.q_five_external_approve = 'Y' 
      OR q_five_internal_table.q_five_internal_approve = 'Y' )

注意我已经更改了第二个查询中列的顺序以匹配第一个查询的类型。

Answer 2

如果我们假设查询的最终目标是在下表中找到parts.id，那么您更新的查询似乎是正确的（语义上）： external_reports，internal_reports，five_way_external_reports，five_way_internal_reports

在组合查询1和查询2的行时将使用Union。

但是，如果您要查找匹配的列（join子句），则使用JOIN而不是UNION。

另外，请为您的查询尝试使用EXPLAIN和EXPLAIN EXTENDED前缀来理解查询计划。

Answer 3

特别感谢@ dnoeth。伟大的人。

修改后的SQL是，

select q_internal_external_table.*,q_five_internal_external_table.* from         
(select q_internal_table.q_part_id, 
q_external_table.q_external_id,q_external_table.q_external_approve, 
q_external_table.q_order_id,q_internal_table.q_internal_id, 
q_internal_table.q_internal_approve from(SELECT parts.id as 
q_part_id,parts.order_id as q_order_id,external_reports.id as 
q_external_id,external_reports.approved as q_external_approve from parts 
LEFT join external_reports on(parts.id=external_reports.part_id)) 
q_external_table LEFT join (SELECT parts.id as q_part_id,internal_reports.id 
as q_internal_id,internal_reports.approved as q_internal_approve from parts 
LEFT join internal_reports on(parts.id=internal_reports.part_id)) 
q_internal_table on(q_external_table.q_part_id=q_internal_table.q_part_id) 
where (q_external_table.q_external_approve='Y' or 
q_internal_table.q_internal_approve='Y')) q_internal_external_table LEFT 
join (select q_five_internal_table.q_five_part_id, 
q_five_internal_table.q_five_internal_id, 
q_five_internal_table.q_five_internal_approve, 
q_five_external_table.q_five_order_id, 
q_five_external_table.q_five_external_id, 
q_five_external_table.q_five_external_approve from (SELECT parts.id as 
q_five_part_id,parts.order_id as q_five_order_id, 
five_way_external_reports.id as q_five_external_id, 
five_way_external_reports.approved as q_five_external_approve from parts 
LEFT join five_way_external_reports on(parts.id= 
five_way_external_reports.part_id)) q_five_external_table LEFT join (SELECT 
parts.id as q_five_part_id,five_way_internal_reports.id as 
q_five_internal_id,five_way_internal_reports.approved as 
q_five_internal_approve from parts LEFT join five_way_internal_reports 
on(parts.id=five_way_internal_reports.part_id)) q_five_internal_table on 
(q_five_external_table.q_five_part_id=q_five_internal_table.q_five_part_id) 
where (q_five_external_table.q_five_external_approve='Y' or 
q_five_internal_table.q_five_internal_approve='Y')) 
q_five_internal_external_table on (q_internal_external_table.q_part_id 
=q_five_internal_external_table.q_five_part_id)

答案:(我想要的）

将2个内连接结果加入到一个结果中

3 个答案: