Question

嗨，这是我创建的用于从历史记录表中获取记录的查询。此查询工作正常，但执行时间过多，因为它从表中选择了两次数据，并且该表具有20密耳或以上的记录。所以我想优化它。我将尝试解释此查询的作用以及我想要实现的目的。我想从表中为每个ID（ActivityId）选择两行，第一行是数据最小的地方，第二行是日期最大的地方，所以我可以看到在此期间发生了多少进展。现在我正在做的是首先选择日期最小的数据作为CTE，然后选择日期最大的数据作为CTE2。我可以在单个CTE中选择两行，但无法从两行中获得一条记录。就像我只需要最大日期行中的“进度和计划字段”，然后选择所有其他字段（大多数字段在两行中都是公用的）。所以我怎么能做到这一点。请根据需要进行澄清。

CTE：

WITH cte AS 
( 
          SELECT    Row_number() OVER (partition BY pmaph.activityid ORDER BY date)    r1, 
                    pma.planenddate                                                 AS planenddate ,
                    pma.planstartdate                                               AS planstartdate,
                    pmaph.activityid, 
                    pmaph.projectmilestoneactivproghist_id                                                 AS promileavtiid,
                    umd.uom_name                                                                           AS uomname,
                    pmm.milestonename                                                                      AS milestonename,
                    pma.activityname                                                                       AS activityname ,
                    pmp.projectname                                                                        AS projectname,
                    Replace((Rtrim(Ltrim(CONVERT(VARCHAR(12),Cast(pmaph.date AS DATETIME),106)))),' ','-') AS rdate, 
                    Isnull(pmaph.actual_progress,0)                                                        AS actualprogress,
                    Isnull(pmaph.planned_progress,0)                                                       AS plannedprogress
          FROM      projectmilestoneactivityprogresshistory                                                AS pmaph
          LEFT JOIN dbo.pm_project                                                                         AS pmp
          ON        pmaph.projectid=pmp.projectid 
          LEFT JOIN dbo.pm_activity AS pma 
          ON        pmaph.activityid=pma.activityid 
          LEFT JOIN dbo.pm_milestone AS pmm 
          ON        pmaph.milestoneid=pmm.milestoneid 
          LEFT JOIN dbo.uomdetail AS umd 
          ON        pma.uom_id=umd.uom_id 
          WHERE     pmaph.client_id=1030), cte2 AS( r2,isnull(pmaph.actual_progress,0) AS actualprogress, isnull(pmaph.planned_progress,0) AS plannedprogress, replace((rtrim(ltrim(CONVERT(varchar(12), cast(pmaph.date AS datetime),106)))),' ','-') AS rdate,pmaph.activityid FROM projectmilestoneactivityprogresshistory AS pmaph WHERE pmaph.client_id=1030)
SELECT cte2.rdate           AS todate, 
       cte2.actualprogress  AS end_actualprogress, 
       cte2.plannedprogress AS end_plannedprogress, 
       cte.actualprogress   AS start_actualprogress, 
       cte.plannedprogress  AS start_plannedprogress, 
       cte.rdate            AS fromdate , 
       cte.planenddate, 
       cte.planstartdate, 
       cte.activityid, 
       cte.uomname, 
       cte.milestonename, 
       cte.activityname, 
       cte.projectname 
FROM   cte 
JOIN   cte2 
ON     cte.activityid= cte2.activityid 
WHERE  cte.r1=1 
AND    cte2.r2=1

如何自行加入CTE？

0 个答案: