Question

我遇到以下查询的性能问题，我想获得一些有关销售线和每个销售线的信息，我想知道最后一个日期是否已收到库存：

SELECT        XAL_SUPERVISOR.SALESTABLE.SALESNUMBER, XAL_SUPERVISOR.SALESTABLE.DEBTORACCOUNT, XAL_SUPERVISOR.SALESTABLE.DELIVERYNAME, 
                     XAL_SUPERVISOR.SALESTABLE.DELIVERYADDRESS3, XAL_SUPERVISOR.SALESTABLE.REQUISNUMBER, XAL_SUPERVISOR.SALESTABLE.CUSTOMERREF, 
                     XAL_SUPERVISOR.SALESTABLE.ROUTE, XAL_SUPERVISOR.SALESTABLE.ROUTENUMBER, XAL_SUPERVISOR.SALESTABLE.CMPVWSTATUS, 
                     XAL_SUPERVISOR.SALESTABLE.CMPLOGISTIEK, XAL_SUPERVISOR.SALESTABLE.USVEHICLE, XAL_SUPERVISOR.SALESTABLE.ELCSALSTCALL, 
                     XAL_SUPERVISOR.SALESTABLE.ELCSALSTOK, XAL_SUPERVISOR.SALESTABLE.ELCEDICODE, XAL_SUPERVISOR.SALESTRANS.ITEMNUMBER, 
                     XAL_SUPERVISOR.STOCKTABLE.ITEMNAME, XAL_SUPERVISOR.SALESTRANS.QTYORDERED, XAL_SUPERVISOR.SALESTRANS.STOCKLOC AS REGELLOC, 
                     XAL_SUPERVISOR.STOCKTABLE.STOCKLOC AS STDLOC, XAL_SUPERVISOR.SALESTABLE.DELIVERYDATE, XAL_SUPERVISOR.SALESTABLE.DATASET, 
                     XAL_SUPERVISOR.SALESTABLE.CMPCORRECTIE, XAL_SUPERVISOR.SALESTRANS.ELCORGQTYORDERED AS ORG_BESTELD, 
                     XAL_SUPERVISOR.STOCKTABLE.CMPVERVALLEN,
                         (SELECT        (SUM(STS.ENTEREDQTY) + SUM(STS.RECEIVED) - SUM(STS.DRAWN))
                           FROM            XAL_SUPERVISOR.STOCKSUM STS
                           WHERE        STS.ITEMNUMBER = XAL_SUPERVISOR.SALESTRANS.ITEMNUMBER AND STS.DATASET = 'CMP'
                           GROUP BY STS.ITEMNUMBER) AS VOORRAAD,
                         (SELECT        SUM(STS.ORDERED)
                           FROM            XAL_SUPERVISOR.STOCKSUM STS
                           WHERE        STS.ITEMNUMBER = XAL_SUPERVISOR.SALESTRANS.ITEMNUMBER AND STS.DATASET = 'CMP'
                           GROUP BY STS.ITEMNUMBER) AS BESTELD,
                         (SELECT        SUM(STS.RESERVPHYSICAL)
                           FROM            XAL_SUPERVISOR.STOCKSUM STS
                           WHERE        STS.ITEMNUMBER = XAL_SUPERVISOR.SALESTRANS.ITEMNUMBER AND STS.DATASET = 'CMP'
                           GROUP BY STS.ITEMNUMBER) AS GERESERVEERD,
                         (SELECT        DDT.QTY
                           FROM            XAL_SUPERVISOR.DEBDLVTRANS DDT
                           WHERE        DDT.TRANSID = XAL_SUPERVISOR.SALESTRANS.TRANSID AND DDT.DATASET = 'CMP') AS PAKBONAANTAL,
                         (SELECT        DIT.QTY
                           FROM            XAL_SUPERVISOR.DEBINVTRANS DIT
                           WHERE        DIT.TRANSID = XAL_SUPERVISOR.SALESTRANS.TRANSID AND DIT.DATASET = 'CMP') AS FACTUURAANTAL,
                         (SELECT        MAX(ST.DATEPHYSICAL)
                           FROM            XAL_SUPERVISOR.STOCKTRANS ST
                           WHERE        ST.ITEMNUMBER = XAL_SUPERVISOR.SALESTRANS.ITEMNUMBER AND ST.DATASET = 'CMP' AND ST.StatusInFlow < 3 AND ST.DCType = 2) 
                     AS LTSTGELEVERD
FROM            XAL_SUPERVISOR.SALESTABLE, XAL_SUPERVISOR.SALESTRANS, XAL_SUPERVISOR.STOCKTABLE
WHERE        XAL_SUPERVISOR.SALESTABLE.DATASET = XAL_SUPERVISOR.SALESTRANS.DATASET AND 
                     XAL_SUPERVISOR.SALESTABLE.SALESNUMBER = XAL_SUPERVISOR.SALESTRANS.SALESNUMBER AND 
                     XAL_SUPERVISOR.SALESTRANS.ITEMNUMBER = XAL_SUPERVISOR.STOCKTABLE.ITEMNUMBER AND 
                     XAL_SUPERVISOR.SALESTRANS.DATASET = XAL_SUPERVISOR.STOCKTABLE.DATASET AND (XAL_SUPERVISOR.SALESTABLE.DELIVERYDATE = :Leverdatum) AND 
                     (XAL_SUPERVISOR.SALESTABLE.DATASET = 'CMP') AND (XAL_SUPERVISOR.SALESTABLE.CMPCORRECTIE = 0)

这部分减慢速度（没有它在<10秒内运行）：

   (SELECT        MAX(ST.DATEPHYSICAL)
                           FROM            XAL_SUPERVISOR.STOCKTRANS ST
                           WHERE        ST.ITEMNUMBER = XAL_SUPERVISOR.SALESTRANS.ITEMNUMBER AND ST.DATASET = 'CMP' AND ST.StatusInFlow < 3 AND ST.DCType = 2) 
                     AS LTSTGELEVERD

当我在SQL中运行它时，我看到它获取主查询然后暂停很长时间才能获取上面的子查询？

Answer 1

如果从.net或coldfusion等应用程序运行此查询，则可以单独运行查询并将其加入应用程序中。使用.net，它将成为DataTable和coldfusion的linq，它将是查询查询。

您可以在存储过程中执行相同的操作。使用子查询中的数据填充临时表，然后将其连接到临时表。

虽然这些事情都是违反直觉的，甚至可能代表最坏的做法，但有时它们适合当前的情况。

Answer 2

SELECT子句中的子查询往往表现不佳一种改进方法是使用内联视图或WITH子句来计算每个ITEMNUMBER的最大值，然后加入它。

WITH datephysical_max as
    (SELECT Max(ST.datephysical) max_ , ST.itemnumber 
        FROM   xal_supervisor.stocktrans ST 
        WHERE  
               AND ST.dataset = 'CMP' 
               AND ST.statusinflow < 3 
               AND ST.dctype = 2
        GROUP BY )  
SELECT 
      ....,
      st.LTSTGELEVERD
FROM   xal_supervisor.salestable 
       inner join xal_supervisor.salestrans 
               ON xal_supervisor.salestable.dataset = 
                  xal_supervisor.salestrans.dataset 
                  AND xal_supervisor.salestable.salesnumber = 
                      xal_supervisor.salestrans.salesnumber 
                  AND xal_supervisor.salestrans.itemnumber = 
                      xal_supervisor.stocktable.itemnumber 
       inner join xal_supervisor.stocktable 
               ON xal_supervisor.salestrans.dataset = 
                  xal_supervisor.stocktable.dataset 
       INNER JOIN datephysical_max st
               ON ST.itemnumber = xal_supervisor.salestrans.itemnumber 
WHERE  ( xal_supervisor.salestable.deliverydate = :Leverdatum ) 
       AND ( xal_supervisor.salestable.dataset = 'CMP' ) 
       AND ( xal_supervisor.salestable.cmpcorrectie = 0 )

Answer 3

您可以尝试以下几种方法：

第四个和第五个子查询只获得一个标量值，因此可以将它们放入查询的主体中。看起来您在这里使用子查询来避免使用LEFT JOIN。
可以使用公用表表达式（CTE）组合第一，第二，第三和第六子查询，也称为Oracle WITH子句。与其他子查询值一样，现在必须使用LEFT JOIN合并这些值。

此外，如果您使用ANSI连接语法，这会更容易。这是答案（尽管注意我已经遗漏了很多“旁观者”列，所以它会有点紧凑;如果这个解决方案适合你，你可以添加它们）：

WITH StkSum AS (
  SELECT
    STS.ITEMNUMBER,
    SUM(STS.ENTEREDQTY) + SUM(STS.RECEIVED) - SUM(STS.DRAWN) AS VOORRAAD,
    SUM(STS.ORDERED) AS BESTELD,
    SUM(STS.RESERVPHYSICAL) AS GERESERVEERD,
    MAX(ST.DATEPHYSICAL) AS LTSTGELEVERD
  FROM XAL_SUPERVISOR.STOCKSUM STS
  INNER JOIN XAL_SUPERVISOR.STOCKTRANS ST ON STS.ITEMNUMBER = ST.ITEMNUMBER
  WHERE STS.DATASET = 'CMP'
    AND ST.DATASET = 'CMP'
    AND ST.StatusInFlow < 3
    AND ST.DCType = 2
)
SELECT
  XAL_SUPERVISOR.SALESTABLE.SALESNUMBER,
  ... all those SALESTABLE and SALESTRANS and STOCKTABLE columns ...,
  StkSum.VOORRAAD,
  StkSum.BESTELD,
  StkSum.GERESERVEERD,
  NVL(XAL_SUPERVISOR.DEBDLVTRANS.QTY, 0) AS PAKBONAANTAL,
  NVL(XAL_SUPERVISOR.DEBINVTRANS.QTY, 0) AS FACTUURAANTAL,
  StkSum.LTSTGELEVERD
FROM XAL_SUPERVISOR.SALESTABLE
INNER JOIN XAL_SUPERVISOR.SALESTRANS ON
  SalesTable.DataSet = SalesTrans.DataSet AND
  SalesTable.SalesNumber = SalesTrans.SalesNumber
INNER JOIN XAL_SUPERVISOR.STOCKTABLE ON
  SalesTrans.ItemNumber = StockTable.ItemNumber AND
  SalesTrans.DataSet = StockTable.DataSet
LEFT OUTER JOIN StkSum ON StkSum.ITEMNUMBER = SalesTrans.ITEMNUMBER
LEFT OUTER JOIN XAL_SUPERVISOR.DEBDLVTRANS DDT ON DDT.TRANSID = SalesTrans.TRANSID
LEFT OUTER JOIN XAL_SUPERVISOR.DEBINVTRANS DIT ON DIT.TRANSID = SalesTrans.TRANSID
WHERE
  (XAL_SUPERVISOR.SALESTABLE.DELIVERYDATE = :Leverdatum) AND 
  (XAL_SUPERVISOR.SALESTABLE.DATASET = 'CMP') AND
  (XAL_SUPERVISOR.SALESTABLE.CMPCORRECTIE = 0) AND
  DDT.DATASET = 'CMP' AND
  DIT.DATASET = 'CMP'

最后，请注意由于表格和列数和条件的绝对数量，如果上面的查询是100％正确，我会感到震惊。我尽我所能，但我最好的可能还不够好:)可能需要Tweakage。

Answer 4

你的选择会减慢查询的速度，使得速度变慢：

数学（小于）可以不使用案例索引。考虑
如果列表很小，则更改为列表
如果您没有如下索引，那么它会很慢

一个打开（ST.item_number，ST.dataset，ST.status_in_flow，ST.dctype）一个在XAL_SUPERVISOR（itemNumber）上一个on datephysical可以被max使用，因为它会导致order by。
考虑首先使用查询运行所有where子句，然后根据它执行max。

如果不使用索引，原因有很多。数学在where子句中，如果大行数，则明确考虑第1项，因此将使用索引。此外，如果列可以为null，to_upper等，则可以使用基于函数的索引。

查询子查询执行很糟糕

4 个答案: