如何在oracle中使用CASE查询

Question

您好我正在尝试运行此查询，但在where语句中，Case正在发出错误。我要做的是，如果i_id is >= 284在cnint <=65之后附加另一个and，则将Select cnint as Id, cnabbv as Code, rtrim(cnname) as Name, i_id as CId, cntry as CCode from money.country where cntype = 1 and (CASE WHEN i_id = 284 THEN cnint <= 65 ELSE cnint > 65 END) order by cnname; 附加到查询中。此查询位于存储过程中。

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此查询位于存储过程中。

Answer 1

那里不支持。试试这个：

Select cnint as Id, cnabbv as Code, rtrim(cnname) as Name, i_id as CId, cntry as CCode 
from money.country where cntype = 1 and
((i_id = 284 AND cnint <= 65) OR (coalesce(i_id, 0) != 284 and cnint > 65))
order by cnname;

Answer 2

你可以用case这样的

来完成

select cnint as Id, 
       cnabbv as Code, 
       rtrim(cnname) as Name, 
       i_id as CId, 
       cntry as CCode 
from money.country 
where cntype = 1 and ( ( i_id = 284 AND cnint <= 65 ) OR (coalesce(i_id, 0) != 284 and cnint>65) )
order by cnname;

当case返回标量值时，您可以使用case这样做 但是case

更具可读性

   select cnint as Id, 
           cnabbv as Code, 
           rtrim(cnname) as Name, 
           i_id as CId, 
           cntry as CCode 
    from money.country 
    where cntype = 1  AND 1 = (CASE WHEN (i_id = 284 AND cnint <= 65 ) OR (coalesce(i_id, 0) != 284 and cnint >65)  
                                    THEN 1
                                    ELSE 0 
                               END)
order by cnname;