Question

 SELECT p.ID, Name
   FROM Policies p
        INNER JOIN ProgramYears py ON p.ProgramYearID = py.id
        INNER JOIN (SELECT MemberID, max(EffectiveDate) AS EffectiveDate
                      FROM Policies
                     GROUP BY MemberID) TEMP
                ON p.memberid = TEMP.MemberID
               AND p.EffectiveDate = TEMP.effectivedate
               AND p.memberid NOT IN (SELECT MemberID
                                        FROM InvoiceDetail
                                       WHERE ProgramYear = NAME)

Answer 1

NOT EXISTS通常是NOT IN的更好替代品，但您的选择很大程度上取决于数据以及表和索引的结构。

尝试下面的查询，但将其执行计划与当前查询的执行计划进行比较;对一个场景有效的方法可能不适用于另一个场景。

 SELECT p.ID, Name
   FROM Policies p
        INNER JOIN ProgramYears py ON p.ProgramYearID = py.id
        INNER JOIN (SELECT MemberID, max(EffectiveDate) AS EffectiveDate
                      FROM Policies
                     GROUP BY MemberID) TEMP
                ON p.memberid = TEMP.MemberID
                   AND p.EffectiveDate = TEMP.effectivedate
  WHERE NOT EXISTS
            (SELECT MemberID
               FROM InvoiceDetail AS ID
              WHERE ID.ProgramYear = NAME
                AND p.MemberId = ID.MemberId)

Answer 2

您可以尝试：

 SELECT a.ID, a.Name
   FROM (SELECT p.ID, Name,
                ROW_NUMBER()OVER(PARTITION BY p.memberid ORDER BY p.EffectiveDate DESC) AS rnk
           FROM Policies p
                INNER JOIN ProgramYears py ON p.ProgramYearID = py.id
          WHERE NOT EXISTS (SELECT MemberID
                              FROM InvoiceDetail AS ID
                             WHERE ID.ProgramYear = NAME
                               AND p.MemberId = ID.MemberId)
        ) a
  WHERE a.rnk = 1

任何人都可以帮我优化我的查询吗？

2 个答案: