使用日期字段来匹配SQL查询

Question

我有点问题围绕着这个不断变化的维度的逻辑。我想将以下两张表联系起来。我需要根据ID和生效日期将成本期间事实表与成本维度相匹配。

正如您所看到的 - 如果月份和年份字段大于其关联成本维度的生效日期，则应采用该值。一旦将新的生效日期输入到维度中，它应该将该值用于大于所述日期的任何时间段。

编辑：我对缺乏细节表示歉意，但成本维度实际上会有一个唯一的索引值，并且匹配引用的变化字段为资源，项目，成本。我试图将您提供的查询与我的字段进行匹配，但是我收到了错误的输出。

FYI：命名约定的变化：EngagementId是标识，资源是ConsultantId，和项目是专案编号

我已经改变了下面的图片，这里是我的查询

 ,_cte(HoursWorked, HoursBilled, Month, Year, EngagementId, ConsultantId, ConsultantName, ProjectId, ProjectName, ProjectRetainer, RoleId, Role, Rate, ConsultantRetainer, Salary, amount, EffectiveDate) 
    as 
    (
    select sum(t.Duration), 0, Month(t.StartDate), Year(t.StartDate), t.EngagementId, c.ConsultantId, c.ConsultantName, c.ProjectId, c.ProjectName, c.ProjectRetainer, c.RoleId, c.Role, c.Rate, c.ConsultantRetainer, 
c.Salary, 0, c.EffectiveDate 
     from timesheet t 
     left join Engagement c on t.EngagementId = c.EngagementId and Month(c.EffectiveDate) = Month(t.EndDate) and Year(c.EffectiveDate) = Year(t.EndDate) 
     group by Month(t.StartDate), Year(t.StartDate), t.EngagementId, c.ConsultantName, c.ConsultantId, c.ProjectId, c.ProjectName, c.ProjectRetainer, c.RoleId, c.Role, c.Rate, c.ConsultantRetainer, 
c.Salary, c.EffectiveDate 

    ) 
    select * from _cte where EffectiveDate is not null 
    union 
    select _cte.HoursWorked, _cte.HoursBilled, _cte.Month, _cte.Year, _cte.EngagementId, _cte.ConsultantId, _cte.ConsultantName, _cte.ProjectId, _Cte.ProjectName, _cte.ProjectRetainer, _cte.RoleId, _cte.Role, sub.Rate, _cte.ConsultantRetainer,_cte.Salary, _cte.amount, sub.EffectiveDate 
     from _cte 
     outer apply (
       select top 1 EffectiveDate, Rate 
       from Engagement e 
       where e.ConsultantId = _cte.ConsultantId and e.ProjectId = _cte.ProjectId and e.RoleId = _cte.RoleId 
       and Month(e.EffectiveDate) < _cte.Month and Year(e.EffectiveDate) < _cte.Year 
       order by EffectiveDate desc 
      ) sub 
    where _cte.EffectiveDate is null 

例子：

我正在努力编写与此一致的查询。起初，我试图按最大日期进行分组。但是，当我执行加入时，我获得了每个单一时期（甚至是生效日期之前的最高生效日期）的最高生效日期。

这是可以在查询中完成的事情，还是我应该专注于目标表的增量更新，以便过去的任何有效日期/时间段都是独立的？

任何提示将是伟大的！

感谢， 钱宁

Answer 1

试试这个：

; with _CTE as(
    select p.* , c.EffectiveDate, c.Cost 
    from period p 
     left join CostDimension c on p.id = c.id and p.Month = DATEPART(month, c.EffectiveDate) and p.year = DATEPART (year, EffectiveDate) 
) 
select * from _CTE Where EffectiveDate is not null 

Union 

select _CTE.id, _CTE.Month, _CTE.Year, sub.EffectiveDate, sub.Cost 
from _CTE 
    outer apply (select top 1 EffectiveDate, Cost 
        from CostDimension as cd 
        where cd.Id = _CTE.id and cd.EffectiveDate < DATETIMEFROMPARTS(_CTE.Year, _CTE.Month, 1, 0, 0, 0, 0) 
        order by EffectiveDate desc 
       ) sub 
where _Cte.EffectiveDate is null