獲取客戶，只有當他們被09月

Question

天生我有一個消息「無效的關係運算符」

select distinct ig.describe from info_groupe ig 
inner join client_info ki on (ig.id=ki.id_info_group) 
where exists (select * from client k inner join client_contact kk 
on (k.id=kk.id_client) where kk.location='B' 
and kk.type_contact= 'EMAIL' 
AND substr(date, 4, 2), 
'dd.mm.yyyy'), 'MM' ='09' 
order by describe desc; 

除了每月的問題，我必須滿足的條件是，location ="B"和type_contact = "EMAIL"。 我想是爲了顯示「describe」與條件位置B和型接觸=電子郵件爲有日期的所有客戶端（例如88年9月1日）09月

Answer 1

您可以使用EXTRACT(MONTH FROM <date column>)：

select distinct ig.describe 
from info_groupe ig 
     inner join client_info ki 
     on (ig.id=ki.id_info_group) 
where exists (select * 
       from client k 
         inner join client_contact kk 
         on (k.id=kk.id_client) 
       where kk.location='B' 
       and kk.type_contact= 'EMAIL' 
       AND EXTRACT(MONTH FROM date) = 9 
      ) 
order by describe desc; 

Answer 2

試試這個：

select distinct ig.describe from info_groupe ig 
inner join client_info ki on (ig.id=ki.id_info_group) 
where exists (select * from client k inner join client_contact kk 
       on (k.id=kk.id_client) where kk.location='B' 
       and kk.type_contact= 'EMAIL' 
       AND to_char(date,'MM') ='09' 
       AND ki.id = kk.id_client) 
order by describe desc 

我假設你有client_info中的客戶端id列，我把它稱爲id_client，如果它不同，那麼改變它。

我用to_char（date，'MM'）來得到月份。