mysql - 在 postgres 的不同列中获取联合的输出

Question

我在一家拨号器公司工作，我们有一个调用历史记录表，其中有不同的列。

现在我想获取一个可以计算的输出:

已接通的外拨电话总数

Select count(*) 
from call_history 
where system_disposition = 'CONNECTED' and call_type = 'OUTBOUND' 

系统检测到的 AMD 总数

Select count(*) 
from call_history 
where system_disposition = 'CONNECTED'   

AGent 检测到的 AMD 总量

Select count(*) 
from call_history 
system_disposition='CONNECTED' and call_id in (
    select call_id 
    from udh 
    where disposition_code = 'Answering machine'
)

现在，如果我使用 union 命令，所有结果都会出现在一列中，并且使用交叉联接会给出重复输出，即限制 2 给出每个条目两次的输出。

请帮助我进行一个查询，该查询可以告诉我:

出站连接总数 | AMD 系统 | AMD 代理 |泄漏为(AMD 代理/(总计)

Answer 1

您可以合并结果并在单独的列中选择每个结果，如下所示:

Select sum(r1) as result1, sum(r2) as redult2, sum(r3) as result3 from(
Select count(*) as r1, 0 as r2,0 as r3 from call_history where system_disposition='CONNECTED' and call_type='OUTBOUND'
Union
Select 0 as r1,count(*) as r2, 0 as r3 from call_history where system_disposition='CONNECTED')
Union
Select 0 as r1, 0 as r2,count(*) as r3 from call_history system_disposition='CONNECTED' and call_id in (select call_id from udh where disposition_code='Answering machine')
)