Oracle性能调整

我有下面的oracle查询。它需要很长时间才能运行。您能为这个查询建议一些性能调整吗

select ss.registration_id as REGISTRATION_ID,
       ss.batch_id as BATCH_ID
  from submtd_srvc PARTITION(SUBMTD_SRVC_821370) ss,
       (select a.exceptn_criteria_val,
               a.exceptn_criteria_rtrn_val 
          from EXCEPTN_CRITERIA a,
               EXCEPTN_EXPRESSION b
          where a.EXCEPTN_EXPRESSION_ID = b.EXCEPTN_EXPRESSION_ID
            and b.EXCEPTN_EXPRESSION_NAME = 'NC_CUSTOM_REV_CAT'
            and b.IS_CURRENT_INDCTR = 1
            and a.IS_CURRENT_INDCTR = 1) sub_query
  where ss.REVENUE_CD = sub_query.exceptn_criteria_val
    and ss.batch_id =  821370
    and exists (select 'x'
                  from submtd_srvc PARTITION(SUBMTD_SRVC_821370) ss2,
                       (select a.exceptn_criteria_val,
                               a.exceptn_criteria_rtrn_val 
                          from EXCEPTN_CRITERIA a,
                               EXCEPTN_EXPRESSION b
                          where a.EXCEPTN_EXPRESSION_ID = b.EXCEPTN_EXPRESSION_ID
                            and b.EXCEPTN_EXPRESSION_NAME = 'NC_CUSTOM_REV_CAT'
                            and b.IS_CURRENT_INDCTR = 1
                            and a.IS_CURRENT_INDCTR = 1) sub_query2
                  where ss2.REVENUE_CD = sub_query2.exceptn_criteria_val
                    and ss2.registration_id = ss.registration_id
                    and ss2.batch_id = ss.batch_id
                    and ss2.batch_id = 821370
                    and sub_query2.exceptn_criteria_rtrn_val <> sub_query.exceptn_criteria_rtrn_val)
  Order By Ss.Registration_Id,
           ss.batch_id;

---

如果我理解正确，您可以使用关联子查询查找具有多个不同exceptn_criteria_rtrn_val值的行。如果我是对的，将更好地使用分析函数：

select vw.registration_id as REGISTRATION_ID, vw.batch_id as BATCH_ID
from
 (select ss.registration_id as REGISTRATION_ID, ss.batch_id as BATCH_ID
        ,count(distinct sub_query.exceptn_criteria_rtrn_val) over(partition by ss.registration_id, ss.batch_id) as cnt
    from submtd_srvc PARTITION(SUBMTD_SRVC_821370) ss,
         (select a.exceptn_criteria_val, a.exceptn_criteria_rtrn_val
            from EXCEPTN_CRITERIA a, EXCEPTN_EXPRESSION b
           where a.EXCEPTN_EXPRESSION_ID = b.EXCEPTN_EXPRESSION_ID
             and b.EXCEPTN_EXPRESSION_NAME = 'NC_CUSTOM_REV_CAT'
             and b.IS_CURRENT_INDCTR = 1
             and a.IS_CURRENT_INDCTR = 1) sub_query
   where ss.REVENUE_CD = sub_query.exceptn_criteria_val
     and ss.batch_id = 821370) vw
where cnt > 1
Order By vw.Registration_Id, vw.batch_id;

---

如果我理解正确，您可以使用关联子查询查找具有多个不同exceptn_criteria_rtrn_val值的行。如果我是对的，将更好地使用分析函数：

select vw.registration_id as REGISTRATION_ID, vw.batch_id as BATCH_ID
from
 (select ss.registration_id as REGISTRATION_ID, ss.batch_id as BATCH_ID
        ,count(distinct sub_query.exceptn_criteria_rtrn_val) over(partition by ss.registration_id, ss.batch_id) as cnt
    from submtd_srvc PARTITION(SUBMTD_SRVC_821370) ss,
         (select a.exceptn_criteria_val, a.exceptn_criteria_rtrn_val
            from EXCEPTN_CRITERIA a, EXCEPTN_EXPRESSION b
           where a.EXCEPTN_EXPRESSION_ID = b.EXCEPTN_EXPRESSION_ID
             and b.EXCEPTN_EXPRESSION_NAME = 'NC_CUSTOM_REV_CAT'
             and b.IS_CURRENT_INDCTR = 1
             and a.IS_CURRENT_INDCTR = 1) sub_query
   where ss.REVENUE_CD = sub_query.exceptn_criteria_val
     and ss.batch_id = 821370) vw
where cnt > 1
Order By vw.Registration_Id, vw.batch_id;

您可以将EXISTS替换为GROUP BY，并具有：

我还删除了所有子查询，并使用了ANSI标准联接，而不是传统的Oracle联接。

您可以用GROUP BY和HAVING替换EXISTS：

---

我还去掉了所有的子查询，并使用了ANSI标准联接，而不是传统的Oracle联接。

如果您可以发布解释计划以及表和索引的结构，这将非常有用。我个人将去掉exists子句并使用join。在我的情况下，它工作得更快。除此之外，请查看解释计划，并找到您在哪里进行全表扫描。如果可能的话，为它们创建索引。发布查询通常没有足够的信息；你可能会发现一些你应该发布的提示。如果你可以发布你的解释计划以及你的表和索引的结构，这将是非常有用的。我个人会去掉exists子句并使用join。在我的情况下，它工作得更快。除此之外，请查看解释计划，并找到您在哪里进行全表扫描。如果可能的话，为它们创建索引。发布查询通常没有足够的信息；你可能会发现一些你应该发布的提示。