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ORACLE MERGE INTO DELETE 注意源表和目标表数据都要唯一 merge into PERSONCERTIFICATEBAK b using (select ids from person_cer_dele ) u on (b.id = u.ids) when matched then update set b.personguid = b.personguid delet...

生成执行计划 explain plan for select * from xxxx where xxx = xxx; 查看索引使用明细 select * from table(dbms_xplan.display);