Oracle 查询性能优化

Posted 2023-04-14

【中文标题】Oracle 查询性能优化

【英文标题】：Oracle Query Performance Optimization

【发布时间】：2020-06-10 21:05:37

【问题描述】：

我目前正在优化以下查询，运行时间超过 60 分钟。查询中提供的日期由在执行期间计算日期的变量替换。目标是让此查询在 10 分钟内运行。

SELECT
   clm.clcl_payee_pr_id, 
   clm.sbsb_ck, 
   clm.clcl_id, 
   clm.meme_ck, 
   clm.clcl_paid_dt, 
   Row_number() 
     OVER ( 
       ORDER BY clm.clcl_payee_pr_id, clm.sbsb_ck, clm.clcl_id) AS reccount
FROM cmc_mepe_prcs_elig MEPE 
INNER JOIN cmc_meme_member MEME 
        ON MEPE.meme_ck = MEME.meme_ck 
           AND MEPE.grgr_ck = '41' 
INNER JOIN cmc_mepr_prim_prov MEPR 
        ON MEPE.meme_ck = MEPR.meme_ck 
           AND MEPR.grgr_ck = '41' 
INNER JOIN cmc_sbsb_subsc SBSB 
        ON MEME.sbsb_ck = SBSB.sbsb_ck 
           AND SBSB. grgr_ck = '41' 
INNER JOIN cmc_prpr_prov PROV 
        ON MEPR.prpr_id = PROV.prpr_id 
INNER JOIN cmc_prer_relation PRER 
        ON PRER.prpr_id = MEPR.prpr_id 
           AND PRER.prer_prpr_entity = 'I' 
           AND PRER.prer_prpr_id IN ( '02549455' ) 
INNER JOIN cmc_clcl_claim CLM 
        ON MEME.meme_ck = CLM.meme_ck 
           AND CLM.clcl_prpr_id_pcp = MEPR.prpr_id 
INNER JOIN cmc_prpr_prov PRPR 
        ON CLM.prpr_id = PRPR.prpr_id 
INNER JOIN cmc_plds_plan_desc PLDS 
        ON MEPE.cspi_id = PLDS.cspi_id 
INNER JOIN cmc_pdds_prod_desc PDDS 
        ON MEPE.pdpd_id = PDDS.pdpd_id 
WHERE  MEPE.mepe_elig_ind = 'Y' 
AND CLM.clcl_low_svc_dt BETWEEN MEPE.mepe_eff_dt AND MEPE.mepe_term_dt 
AND CLM.clcl_low_svc_dt BETWEEN MEPR.mepr_eff_dt AND MEPR.mepr_term_dt 
AND CLM.clcl_cur_sts = '02' 
AND CLM.clcl_cl_type = 'M' 
AND CLM.clcl_cl_sub_type = 'H' 
AND CLM.grgr_ck IN ( 41 ) 
AND ( PLDS.plds_desc LIKE '%risk%' OR PDDS.pdds_desc LIKE '%risk%' ) 
AND CLM.clcl_paid_dt BETWEEN  '24-APR-19 12.00.00.000000 AM' AND '30-APR-19 11.59.59.997000 PM';

以下是使用的每个表的总行数。

cmc_mepe_prcs_elig: 103,974,973 cmc_meme_member: 22,433,154 cmc_mepr_prim_prov: 53,498,452 cmc_sbsb_subsc: 22,433,154 cmc_prpr_prov: 5,266,062 cmc_prer_relation: 4,735,086 cmc_clcl_claim: 897,405,800 cmc_plds_plan_desc：19,122 cmc_pdds_prod_desc: 4,776

所有这些表都驻留在主数据库中，该数据库是只读的，我不允许创建任何索引来提高性能。唯一的选择是使用提示并玩弄查询。以下是上述查询的当前执行计划。

在性能调整方面我是新手，如果您能告诉我是否应该提供有关表的任何其他信息，以便您就调整查询提出建议，我将不胜感激。

【参考方案1】：

试试下面。一般来说，您可以像我将解释的那样考虑优化：

尽可能避免使用OR 和LIKE 语句。 当您构建一个连接时，您不应交互两个以上的表。（CLM 同时与 MEME 和 MEPR 连接。如果您需要连接这 3 个表，请尝试使用另一个别名（如 CLM2）添加另一个连接，然后加入此其他表的新别名。）

SELECT CLM.CLCL_PAYEE_PR_ID,
       CLM.SBSB_CK,
       CLM.CLCL_ID,
       CLM.MEME_CK,
       CLM.CLCL_PAID_DT,
       ROW_NUMBER ()
          OVER (ORDER BY CLM.CLCL_PAYEE_PR_ID, CLM.SBSB_CK, CLM.CLCL_ID)
          AS RECCOUNT
  FROM CMC_MEPE_PRCS_ELIG MEPE
       INNER JOIN CMC_PLDS_PLAN_DESC PLDS ON MEPE.CSPI_ID = PLDS.CSPI_ID
       INNER JOIN CMC_PDDS_PROD_DESC PDDS ON MEPE.PDPD_ID = PDDS.PDPD_ID
       INNER JOIN CMC_MEME_MEMBER MEME
          ON MEPE.MEME_CK = MEME.MEME_CK AND MEPE.GRGR_CK = '41'
       INNER JOIN CMC_SBSB_SUBSC SBSB
          ON MEME.SBSB_CK = SBSB.SBSB_CK AND SBSB.GRGR_CK = '41'
       INNER JOIN CMC_MEPR_PRIM_PROV MEPR
          ON MEPE.MEME_CK = MEPR.MEME_CK AND MEPR.GRGR_CK = '41'
       INNER JOIN CMC_PRPR_PROV PROV ON MEPR.PRPR_ID = PROV.PRPR_ID
       INNER JOIN CMC_PRER_RELATION PRER
          ON PRER.PRPR_ID = MEPR.PRPR_ID AND PRER.PRER_PRPR_ENTITY = 'I'
       INNER JOIN CMC_PRPR_PROV PRPR ON CLM.PRPR_ID = PRPR.PRPR_ID
       INNER JOIN CMC_CLCL_CLAIM CLM
          ON     MEME.MEME_CK = CLM.MEME_CK
--             AND CLM.CLCL_PRPR_ID_PCP = MEPR.PRPR_ID
 WHERE     MEPE.MEPE_ELIG_IND = 'Y'
       AND CLM.CLCL_LOW_SVC_DT BETWEEN MEPE.MEPE_EFF_DT AND MEPE.MEPE_TERM_DT
       AND CLM.CLCL_LOW_SVC_DT BETWEEN MEPR.MEPR_EFF_DT AND MEPR.MEPR_TERM_DT
       AND CLM.CLCL_CUR_STS = '02'
       AND CLM.CLCL_CL_TYPE = 'M'
       AND CLM.CLCL_CL_SUB_TYPE = 'H'
       AND CLM.GRGR_CK IN (41)
--       AND (PLDS.PLDS_DESC LIKE '%risk%' OR PDDS.PDDS_DESC LIKE '%risk%')
       AND CLM.CLCL_PAID_DT BETWEEN '24-APR-19 12.00.00.000000 AM'
                                AND '30-APR-19 11.59.59.997000 PM'
       AND PRER.PRER_PRPR_ID = '02549455';

【讨论】：

感谢您的建议。我不能更改查询中的 LIKE 子句，因为这是一个基本条件。如果我可以通过创建阶段/临时表来获得相同的结果，我会尝试。