所有 DTM 值的每小时 SQL 计数

Question

我有一个现有的具有 Oracle DTM 格式的值范围，例如 22-NOV-18 12.20.45.430838000

我的目标是在整个值范围内每小时进行一次计数。我想要计算不同日期的所有唯一值。

这被证明是困难的，因为提取函数只能从字段中提取 1 个日期类型，而我需要多个值。

我能够编写以下查询，它为我提供了整个范围内每天的计数。

select trunc(created_dtm), count(*) CreatedCount from

(select ord.order_id, ordser.service_id, ord.product_type, ord.created_dtm ,ord.last_modified_dtm from SCADRON_OWNER.orders ord, SCADRON_OWNER.order_subtype os, SCADRON_OWNER.order_services ordser where ord.order_id = os.order_id and ordser.order_id = ord.order_id and os.subtype = 'FttcActiveLineTakeoverUpgrade' and ord.order_status
= 'Completed' )

group by trunc(created_dtm) order by trunc(created_dtm);

产生这样的结果：

但是，我想对此进行改进，以便我可以计算每小时的所有值，有没有简单的方法可以做到这一点？

Answer 1

我想你想要：

select cast(trunc(created_dtm, 'hh') as timestamp),
       count(*)
from SCADRON_OWNER.orders ord join
     SCADRON_OWNER.order_subtype os
     on ord.order_id = os.order_id join
     SCADRON_OWNER.order_services ordser 
     on ordser.order_id = ord.order_id 
where os.subtype = 'FttcActiveLineTakeoverUpgrade' and 
      ord.order_status = 'Completed' 
group by cast(trunc(created_dtm, 'hh') as timestamp)
order by min(created_dtm);

这会将值转换为时间戳，以便您查看。或者，转换为字符串：

select to_char(created_dtm, 'YYYY-MM-DD HH24') || ':00:00',
       count(*)
from SCADRON_OWNER.orders ord join
     SCADRON_OWNER.order_subtype os
     on ord.order_id = os.order_id join
     SCADRON_OWNER.order_services ordser 
     on ordser.order_id = ord.order_id 
where os.subtype = 'FttcActiveLineTakeoverUpgrade' and 
      ord.order_status = 'Completed' 
group by to_char(created_dtm, 'YYYY-MM-DD HH24')
order by min(created_dtm);