从 SQL 中单列中的过滤值创建多列

Question

我需要一些帮助 我有一个看起来像这样的数据库：

我想分开这个表，为每个队列创建 1 列，并将时间分组以获得一个唯一列表，因为我一次只过滤 24 小时。

预期的结果将是这样的：

到目前为止，我尝试过的代码是：

select intervals,
case when Queue = 'A' then #calls end as queueA#calls,
case when Queue = 'A' then %callsAnswered end as queueA%ans,
case when Queue = 'B' then #calls end as queueB#calls,
case when Queue = 'B' then %callsAnswered end as queueB%ans,
case when Queue = 'C' then #calls end as queueC#calls,
case when Queue = 'C' then %callsAnswered end as queueC%ans
from myTable
group by intervals
order by intervals

但我得到一个空列表，到目前为止只有间隔。 请问你能帮帮我吗？

Answer 1

使用聚合。 如果您每次只有一行，那么：

select intervals,
       max(case when Queue = 'A' then #calls end) as queueA#calls,
       max(case when Queue = 'A' then %callsAnswered end) as queueA%ans,
       max(case when Queue = 'B' then #calls end) as queueB#calls,
       max(case when Queue = 'B' then %callsAnswered) end as queueB%ans,
       max(case when Queue = 'C' then #calls end) as queueC#calls,
       max(case when Queue = 'C' then %callsAnswered end) as queueC%ans
from myTable
group by intervals
order by intervals