在Oracle中合並兩個查詢

Question

我有2個查詢來檢索faultCount和responseCount ，如下所示，它工作正常。

select count(*) as faultCount,
       COMP_IDENTIFIER 
from CORDYS_NCB_LOG 
where AUDIT_CONTEXT='FAULT' 
group by COMP_IDENTIFIER  
order by responseCount;

select count(*) as responseCount,
       COMP_IDENTIFIER 
from CORDYS_NCB_LOG 
where AUDIT_CONTEXT='RESPONSE' 
group by COMP_IDENTIFIER  
order by responseCount;

我需要加入以獲得這樣的列： COMP_IDENTIFIER,faultCount,responseCount 。 以下查詢可以完成這項工作。 但是執行時間很長（> 16秒）。

select count(case AUDIT_CONTEXT when 'FAULT'    then 1 end) as faultCount,
       count(case AUDIT_CONTEXT when 'RESPONSE' then 1 end) as responseCount,
       COMP_IDENTIFIER 
from CORDYS_NCB_LOG 
group by COMP_IDENTIFIER  
order by responseCount;

我正在尋找一個簡單，快速的查詢。 提前致謝。

Answer 1

這可能需要更長的時間，原因之一是您正在讀取CORDYS_NCB_LOG所有行，即使AUDIT_CONTEXT不是FAULT或RESPONSE ，這也是您唯一感興趣的行。

您可以將其添加到現有查詢的WHERE子句中：

select count(case AUDIT_CONTEXT when 'FAULT'    then 1 end) as faultCount,
       count(case AUDIT_CONTEXT when 'RESPONSE' then 1 end) as responseCount,
       COMP_IDENTIFIER 
from CORDYS_NCB_LOG
where AUDIT_CONTEXT in ('FAULT', 'RESPONSE')
group by COMP_IDENTIFIER  
order by responseCount;