Oracle案例：通过添加本地分区索引提高SQL性能

今天接到同事求助，说有一个select query，在Oracle上要跑一分多钟，他希望能在5s内出结果，该sql如下： Select /*+ parallel(s

今天接到同事求助，说有一个select query，在Oracle上要跑一分多钟，，他希望能在5s内出结果，该sql如下：

Select /*+ parallel(src, 8) */ distinct
src.systemname as systemname
, src.databasename as databasename
, src.tablename as tablename
, src.username as username
from meta_dbql_table_usage_exp_hst src
inner join DR_QRY_LOG_EXP_HST rl on
src.acctstringdate = rl.acctstringdate
and src.queryid = rl.queryid
And Src.Systemname = Rl.Systemname
and src.acctstringdate > sysdate - 30
And Rl.Acctstringdate > Sysdate - 30
inner join meta_dr_qry_log_tgt_all_hst tgt on
upper(tgt.systemname) = upper('MOZART')
And Upper(tgt.Databasename) = Upper('GDW_TABLES')
And Upper(tgt.Tablename) = Upper('SSA_SLNG_LSTG_MTRC_SD')
AND src.acctstringdate = tgt.acctstringdate
and rl.statement_id = tgt.statement_id
and rl.systemname = tgt.systemname
And Tgt.Acctstringdate > Sysdate - 30
And Not(
Upper(Tgt.Systemname)=Upper(src.systemname)
And
Upper(Tgt.Databasename) = Upper(Src.Databasename)
And
Upper(Tgt.Tablename) = Upper(Src.Tablename)
)
And tgt.Systemname is not null
And tgt.Databasename Is Not Null
And tgt.tablename is not null
;