IN 子句的 SQL 调优答案

【问题标题】：SQL Tuning for IN ClauseIN 子句的 SQL 调优
【发布时间】：2013-10-10 04:56:55
【问题描述】：

以下 Teradata 查询大约需要 18 秒才能完成。 IN 子句中传递的突出显示的值来自另一个 Oracle 数据库，因此我无法实现与该表的连接。

SELECT distinct sec.SerialNum esn, ef.EngineFamilyCd family, em.EngineModelCd model,
es.EngineSeriesCd series, sac.AircraftTailNum tailNumRef, sec.EnginePositionNum enginePosition,
o1.OrganizationId ownerOrgId, o2.OrganizationId operatorOrgId,
sec.EngineInstallationDttm installedDate, sec.EngineRemovalDttm removalDate,
sec.HardwareConfigNm hardwareConfig, sec.EngineControlNm engineControl,
sec.ApplicationSelectorNm appSelector, sec.EngineMonitorInd engineMonitorInd,
sec.EngineThrustRatingFctr engineThrustRating, sec.StatusDesc engineStatus, sec.n1modifiernum n1modifier
FROM DB_MASTER_BV.SZEngineCurrent sec, 
 DB_MASTER_BV.EngineSeries es,
DB_MASTER_BV.EngineModel em,
DB_Master_BV.EngineFamily ef,
DB_MASTER_BV.SZAircraftCurrent sac, 
 DB_MASTER_BV.Organization o1, 
 DB_MASTER_BV.Organization o2 
 WHERE sec.EngineSeriesCd = es.EngineSeriesCd 
 and es.EngineModelCd = em.EngineModelCd 
 and  em.EngineFamilyCd = ef.EngineFamilyCd 
 and sec.MasterAircraftId = sac.MasterAircraftId 
 and o1.MasterOrganizationId = sec.OwnerMasterOrganizationId 
and o2.MasterOrganizationId = sec.OperatorMasterOrganizationId 
AND (sec.SerialNum in('733276','193283','690168','741471','876374','873383','193386','906397','804314','900116','785670','900399','724321','193488','811373','779917','193699','994688',
'779410','575169','A59299','900206','193297','575484','896359','367230','810105','876485','906385','876484','707149','811222','706801','193596','731949','697881',
'889697','804626','575194','707159','706129','900230','900231','706834','811352','900229','785748','193460','888221','906272','906266','906264','906263','994356',
'194431','731966','892417','811341','577413','741572','575564','889262','706956','876157','900257','900153','706958','706957','960436','892429','892427','900354',
'697138','645655','193352','994337','707189','697833','959190','900246','811317','577437','193643','697976','890692','193229','965579','900137','900135','894897',
'697723','193363','193367','785505','907077','959184','811311','706526','577302','706529','994332','702792','706663','779834','731931','960127','193371','876183',
'741563','193235','803843','577320','994318','907087','741460','907086','959170','994462','900464','193626','877503','643711','811202','811201','704585','193504',
'193500','875246','704876','725834','699783','699780','802380','900304','706885','906191','577773','959152','872574','811435','697388','699381','892485','577698',
'907035','811445','907039','894999','894857','894595','697273','894597','959139','577894','874898','706959','900424','193337','577697','907011','875696','699555',
'699554','575629','906149','906150','193452','962968','811264','811266','962970','875395','699543','575638','906153','857962','896247','858349','779746','906161',
'906928','802857','779640','193424','550309','424520','550305','575608','872517','906169','892196','811386','811385','906173','907220','959234','876666','959231',
'876662','893785','875914','802649','550218','550315','906111','741984','550319','906405','906501','550118','643371','785254','550116','550117','802946','906629',
'907145','550325','550324','906837','550320','906838','702591','550220','550227','906415','690289','906517','704416','731431','550125','959201','906413','994176',
'550333','550140','550337','891651','550141','550338','906746','907269','550132','550137','550138','892914','550342','906123','550153','550345','950923','906129',
'873188','906850','906953','690270','890713','645352','893127','697590','874826','424439','893126','907110','550144','856305','690269','892824','550256','550257',
'906867','907186','960852','720754','960851','906866','888607','805573','811530','960756','872352','550266','550267','550264','811518','888896','906730','994958',
'892247','960970','875186','906987','424124','550232','A59303','702660','875885','811609','888626','424219','906897','994981','731502','697496','695345','962996',
'894371','907153','805541','907154','424337','906613','906615','900512','906610','956141','994611','804582','994718','888648','575219','888756','896973','424395',
'872117','A59227','697616','731380','697614','900161','690410','994213','956155','956154','779492','994231','702876','577248','994727','193818','890879','722243',
'906499','577354','888560','645121','896972','960823','804279','900175','888853','193724','550285','550282','906469','994803','906466','888299','877141','890984',
'695688','994533','888327','A59348','A59346','994410','733116','550296','550290','550292','906478','731763','725658','896408','645145','994751','731654','740358',
'906441','550158','193849','906543','906448','994262','575824','424186','906345','643663','888305','906243','906244','702963','906453','906452','956119','906451',
'956116','950489','550166','906454','367457','896764','575833','994268','906252','994127','733236','906258','956123','550178','994777','956126','956127','956128',
'906786','906788','906687','643290','994631','956225','994632','888574','906365','804228','731599','643682','550182','804369','994784','550186','550183','888826',
'575127','906439','890482','906438','906691','890472','994509','193147','575718','804215','575276','994793','897257'))
and END(sec.EngineValidPd) is until_changed 
 order by esn

另外，如果有超过 1000 条记录，我正在执行 IN 子句如下 AND（sec.SerialNum in（前 999 个记录）或 sec.SerialNum in（下 999 个记录）... OR sec.SerialNum in（剩余记录））请提出比上述查询更快且不会导致 IN 子句中超过 1000 条记录的问题的解决方案

【问题讨论】：

如果您能够从 Oracle 数据库中的数据生成类似上述的查询，为什么不将 SerialNum 放在 Teradata 数据库的临时表中，然后执行对临时表进行连接查询？
这种方法不可扩展，最终会导致问题。我同意 Dan 的观点，您应该将这些值加载到 Teradata 上的临时表中。

标签： oracle teradata

【解决方案1】：

您的 Teradata 版本是什么？

在 TD14 中有一个内置的表格函数来拆分一串值，您可以简单地在一个字符串中传递所有值：

AND sec.SerialNum IN
 (
   SELECT token
   FROM TABLE (STRTOK_SPLIT_TO_TABLE(1, '733276,193283,690168,741471,876374', ',')
        RETURNS (outkey INTEGER,
                 tokennum INTEGER,
                 token VARCHAR(20) CHARACTER SET UNICODE)
              ) AS d
 )

【讨论】：