Question

如果我有这样的桌子。

col1    col2   col3
1       2       3
1       3       2
1       2       1
1       2       2
1       2       3

我只想要col3中所有三个值（1,2,3）的col2值

col2
2

如何获得像这样的人的结果？

Answer 1

select col2
from your_table
group by col2
having count(distinct col3) = (select count(distinct col3) from your_table)

Answer 2

假设1,2和3是col3唯一可接受的值（并且该列不为null），那么你可以这样做：

with sample_data as (select 1 col1, 2 col2, 3 col3 from dual union all
                     select 1 col1, 3 col2, 2 col3 from dual union all
                     select 1 col1, 2 col2, 1 col3 from dual union all
                     select 1 col1, 2 col2, 2 col3 from dual union all
                     select 1 col1, 2 col2, 3 col3 from dual),
             res as (select col1,
                            col2,
                            col3,
                            count(distinct col3) over (partition by col1, col2) cnt_distinct_col3
                     from   sample_data)
select col1,
       col2,
       col3
from   res
where  cnt_distinct_col3 = 3;

      COL1       COL2       COL3
---------- ---------- ----------
         1          2          1
         1          2          2
         1          2          3
         1          2          3

我不确定你的sample_data是否只是从col2开始，或者是col1 + col2;例如，如果样本数据是：

      COL1       COL2       COL3
---------- ---------- ----------
         1          2          3
         1          3          2
         1          2          1
         1          2          2
         1          2          3
         2          3          1
         2          3          3

您是否希望看到col2 = 2和col2 = 3行返回，或者您只希望看到（col1，col2）=（1,2）行返回？

我假设后者，但如果它是前者，那只是从分析函数中的分区子句中取出col1的情况。然后，当然，将选择更改为“选择不同的col2”。

因此，根据您希望如何显示答案，我认为我的查询适用于您希望在结果中显示col1（即未过滤）以及何时希望按特定col1值过滤的情况，例如;

with sample_data as (select 1 col1, 2 col2, 3 col3 from dual union all
                     select 1 col1, 3 col2, 2 col3 from dual union all
                     select 1 col1, 2 col2, 1 col3 from dual union all
                     select 1 col1, 2 col2, 2 col3 from dual union all
                     select 1 col1, 2 col2, 3 col3 from dual union all
                     select 2 col1, 3 col2, 1 col3 from dual union all
                     select 2 col1, 3 col2, 2 col3 from dual union all
                     select 2 col1, 3 col2, 3 col3 from dual union all
                     select 2 col1, 2 col2, 1 col3 from dual union all
                     select 3 col1, 1 col2, 2 col3 from dual union all
                     select 3 col1, 1 col2, 3 col3 from dual),
             res as (select col1,
                            col2,
                            col3,
                            count(distinct col3) over (partition by col1, col2) cnt_distinct_col3
                     from   sample_data)
select distinct col1,
                col2
from   res
where  cnt_distinct_col3 = 3;

      COL1       COL2
---------- ----------
         2          3
         1          2

with sample_data as (select 1 col1, 2 col2, 3 col3 from dual union all
                     select 1 col1, 3 col2, 2 col3 from dual union all
                     select 1 col1, 2 col2, 1 col3 from dual union all
                     select 1 col1, 2 col2, 2 col3 from dual union all
                     select 1 col1, 2 col2, 3 col3 from dual union all
                     select 2 col1, 3 col2, 1 col3 from dual union all
                     select 2 col1, 3 col2, 2 col3 from dual union all
                     select 2 col1, 3 col2, 3 col3 from dual union all
                     select 2 col1, 2 col2, 1 col3 from dual union all
                     select 3 col1, 1 col2, 2 col3 from dual union all
                     select 3 col1, 1 col2, 3 col3 from dual),
             res as (select col1,
                            col2,
                            col3,
                            count(distinct col3) over (partition by col1, col2) cnt_distinct_col3
                     from   sample_data)
select distinct col2
from   res
where  cnt_distinct_col3 = 3
and    col1 = 1;

      COL2
----------
         2

好的，我认为这就是你所追求的：

with sample_data as (select 1 col1, 2 col2, 3 col3 from dual union all
                     select 1 col1, 3 col2, 2 col3 from dual union all
                     select 1 col1, 2 col2, 1 col3 from dual union all
                     select 1 col1, 2 col2, 2 col3 from dual union all
                     select 1 col1, 2 col2, 3 col3 from dual union all
                     select 2 col1, 3 col2, 1 col3 from dual union all
                     select 2 col1, 3 col2, 2 col3 from dual union all
                     select 2 col1, 3 col2, 3 col3 from dual union all
                     select 2 col1, 2 col2, 1 col3 from dual union all
                     select 3 col1, 1 col2, 2 col3 from dual union all
                     select 3 col1, 1 col2, 3 col3 from dual),
             res as (select col1,
                            col2,
                            col3,
                            count(distinct col3) over (partition by col1, col2) cnt_distinct_col3_per_col1col2,
                            count(distinct col3) over (partition by col1) cnt_distinct_col3_per_col1
                     from   sample_data)
select distinct col2
from   res
where  cnt_distinct_col3_per_col1col2 = cnt_distinct_col3_per_col1
and    col1 = 1;

      COL2
----------
         2

这种方式的工作原理是：

查找每个col1值的不同col3值的数量。（因此在上面的例子中，对于col1 = 1，有3个不同的col3值。）
找到每个（col1，col2）配对的不同col3值的数量。（所以在上面的例子中，对于（col1，col2）=（1,2），有3个不同的col3值，而对于（col1，col2）=（1,3），只有1）
选择这两个数字匹配的行。（因此，从上面的例子中，只有（col1，col2）=（1,2）具有与col1 = 1做（3）相同数量的不同值（3）。

如何在列中查找其他列中所有值的常用值？

2 个答案: