部分选择中的SQL查询子查询计数

Question

我有两个表BaseVehicle和Version_Main，它们之间没有关联

我需要获取Count of Count（BaseVehicleId），SUM（BaseVehicleID），Count（NewAddedBaseVehicles），Count（DeletedBaseVehicles）

Count，BaseVehicleID的总和，我可以从下面的查询中获取它，

Select  SUM(DISTINCT CAST(BaseVehicleID as BIGINT)), 
    COUNT(DISTINCT BaseVehicleID) 
    from BaseVehicle

从版本日期起新增基础车辆的数量，我可以从以下查询中获取，

Select COUNT(DISTINCT BaseVehicleId)
from BaseVehicle BV, Version_Main Ver1 
Where Ver.Version_Date IN (Select top 1 Version_Date 
                            from [Version_Main] 
                            order by Version_Date desc) and
BV.InsertDate > Ver.VCDB_Version_Date

从版本日期算起新删除的基础车辆，我可以从以下查询中获取，

Select COUNT(DISTINCT BaseVehicleId)
from BaseVehicle BV, Version_Main Ver
Where Ver.Version_Date IN (Select top 1 Version_Date 
                            from [Version_Main] 
                            order by Version_Date desc) and
BV.InsertDate > Ver.Version_Date and BV.DeleteDate IS NOT NULL

我的表格结构如下，

我可以将这些查询组合在一起查询数据吗？

这将是我预期的结果表

Answer 1

其中一个SQL技巧是将CASE与aggregate function合并。

例如：

select 
count(distinct BV.BaseVehicleID) as Count_BaseVehicle,
sum(distinct CAST(BV.BaseVehicleID as BIGINT)) as Sum_BaseVehicle,
count(distinct case when BV.InsertDate > Ver.VersionDate and BV.DeleteDate is null then BV.BaseVehicleID end) as Count_NewBaseVehicle,
count(distinct case when BV.InsertDate > Ver.VersionDate and BV.DeleteDate is not null then BV.BaseVehicleID end) as Count_DeletedBaseVehicle
from BaseVehicle BV
cross join (select max(VersionDate) as VersionDate from Version_Main) Ver;

虽然我没有得到标识符总和的目的。