筛选出基于列

Question

行重复说我有2列：

Fruit Condition 
apple unripe 
banana ripe 
apple ripe 
banana moldy 
peach moldy 
peach ripe 
apple ripe 
pineapple soldout 

，我只是想知道哪些水果或者是成熟或未成熟和不发霉或售罄（只有苹果）

Select fruit 
from example 
where (condition <> 'moldy' or condition <> 'soldout') 
and (condition = 'ripe' or condition = 'unripe') 
group by fruit 

不工作

Answer 1

您在不使用or。这是错误的方法。

用途：

where not (condition = 'moldy' or condition = 'soldout')

或使用

where (condition <> 'moldy' and condition <> 'soldout')

然后，我假设你想要的只是成熟或未成熟果实。

select distinct Fruit 
from Example E1 
where Condition in ('ripe','unripe') 
and not exists 
    (
    select E2.Fruit 
    from Example E2 
    where E1.Fruit = E2.Fruit 
    and E2.Condition in ('moldy','soldout') 
    ) 

Answer 2

您可以使用HAVING子句CASE EXPRESSION为了这个目的：

SELECT t.fruit FROM YourTable t 
GROUP BY t.fruit 
HAVING COUNT(CASE WHEN t.condition in ('ripe','unripe') THEN 1 END) > 0 
     -- makes sure at least 1 attribute of ripe/unripe exists 
    AND COUNT(CASE WHEN t.condition in ('soldout','moldy') THEN 1 END) = 0 
     -- makes sure no attribute of soldout/moldy exists 

Answer 3

试试这个：

select distinct fruit from example where fruit not in 
(
select fruit from example 
where condition in ('soldout', 'moldy') 
); 

Answer 4

如何：

with example as 
    (select 'apple' as fruit, 'unripe' as condition from dual union all 
     select 'banana', 'ripe' from dual union all 
     select 'apple',  'ripe' from dual union all 
     select 'banana', 'moldy' from dual union all 
     select 'peach',  'moldy' from dual union all 
     select 'peach',  'ripe' from dual union all 
     select 'apple',  'ripe' from dual union all 
     select 'pineapple', 'soldout' from dual) 
select fruit from example 
where condition in ('ripe','unripe') 
minus 
select fruit from example 
where condition in ('moldy','soldout');