Question

超级简化代码：

SELECT lots_of_stuff.
 , A.more_stuff
 , B.stuff
 , C.things
FROM
 table A,
 table B,
 table C,
where (B.more_stuff = A.stuff)
 and things and stuff
 and lots more things
 and this query has so much crap believe me
 and finally
 and count(select c.things from table C where c.things like 'CRED') 
    > count(select c.things from table C where c.things like 'PUR')
;

所以问题是最后一点不起作用（而且我确定我完全做错了，这只是猜测如何做到这一点。）我想知道是否有人可以给我一些建议。

我想要做的只是返回所需字段，以便在特定字段中包含'CRED'的行数大于特定字段中包含'PUR'的行数。（同样的领域，如果这可以简化事情。）我希望他们被退回，无论'CRED'或'PUR'是否是更长的单词（信用/购买）的一部分或独立。他们将永远是全部上限。

编辑：

我正在寻找的只是我指定的那些列

| More_Stuff | Stuff | Things |
|   dshsdh   |  dfh  |  tjra  |
|   ddh      |  ash  |  ytra  |
|   shsdh    |  fgh  |  sayh  |
|   hsdh     |  gnh  |  tshn  |

但仅包含信用代码多于购买计划的客户的行。因此，如果他们在'c.things'中有3个不同的条目，例如“PHONE-CREDIT”或“OFFSET CRED”。 'c.things'中有两个不同的条目，例如“12 M PURCH PLAN”或“PROMO PURCHASE 36”，我希望他们的信息显示出来。因此，当具有任何信用代码的行数大于具有任何购买计划的行数时。我当前的非简化查询已经设置为对所有客户进行排序，我只需要根据此过滤器指定哪些。

Answer 1

我想你想要这样的东西

 WITH cred_count AS
 (
    SELECT index_field, SUM(CASE WHEN field='CRED' THEN 1 ELSE 0 END) AS cred_count
    FROM some_table
    GROUP BY index_field
 ), pur_count AS
 (
    SELECT index_field, SUM(CASE WHEN field='PUR' THEN 1 ELSE 0 END) AS pur_count
    FROM some_table
    GROUP BY index_field
 )
 SELECT somestuff
 FROM some_table
 LEFT JOIN cred_count ON some_table.index_field = cred_count.index_field
 LEFT JOIN pur_count ON some_table.index_field = pur_count.index_field
 WHERE COALESCE(cred_count.cred_count,0) > COALESCE(pur_count.pur_count,0)

注意：您可以将WHEN部分更改为您想要计算的任何内容（例如WHEN field like '%PUR%'将计算包含字符串PUR的行

此外，我假设没有条目计为0 - 您的业务规则可能会有所不同。

Answer 2

这可以使用Oracle中的WITH Clause实现。以下代码可能接近你想要的 -

with ds1 as
(
    SELECT 
       lots_of_stuff
       , A.more_stuff
       , B.stuff
       , C.things,
       count(c.things) AS COUNT_CRED
    FROM
       table A,
       table B,
       table C,
    where 
       (B.more_stuff = A.stuff)
       and things and stuff
       and lots more things
       and this query has so much crap believe me
       and finally
       and c.things like 'CRED%'
   group by 
       lots_of_stuff.
       , A.more_stuff
       , B.stuff
       , C.things
   ),
 ds2 as
 (
    SELECT 
       lots_of_stuff.
       , A.more_stuff
       , B.stuff
       , C.things,
       count(c.things) AS COUNT_PUR
    FROM
       table A,
       table B,
       table C,
    where 
       (B.more_stuff = A.stuff)
       and things and stuff
       and lots more things
       and this query has so much crap believe me
       and finally
       and c.things like 'PUR%'
    group by 
       lots_of_stuff.
       , A.more_stuff
       , B.stuff
       , C.things
)
 SELECT DS1.*, ds2.*
 from ds1, ds2
 where count_cred > COUNT_PUR
 ;

Answer 3

要以较长的单词过滤CRED和PUR，请在查询中使用％等通配符。

like '%CRED%'  -- if CRED can be anywhere in the string
like 'CRED%'  -- if CRED is always at the beginning of the string

请注意，如果它始终位于字符串的开头，则可以使用列上的索引使其运行得更快。

你不能在where子句中使用count（）这样的聚合（除非Oracle支持它吗？）

您可以对行进行分组并使用HAVING，但在您的情况下，实际上更容易在子查询中移动count（）。

   SELECT lots_of_stuff.
 , A.more_stuff
 , B.stuff
 , C.things
FROM
 table A,
 table B,
 table C,
where (B.more_stuff = A.stuff)
 and things and stuff
 and lots more things
 and this query has so much crap believe me
 and finally
 and (select count(c.things) from table C where c.things like '%CRED%') 
    > (select count(c.things) from table C where c.things like '%PUR%')
;

SQL查询;如何仅在一行中的条目数大于另一行中的条目数时显示信息？

3 个答案: