SUM/AVG的优化drop table t purge;create table t as select * from dba_objects;create index idx1_object_id on t(object_id);set autotrace onset linesize 1000set timing onselect sum(object_id) fro...
SUM/AVG的优化drop table t purge;create table t as select * from dba_objects;create index idx1_object_id on t(object_id);set autotrace onset linesize 1000set timing onselect sum(object_id) fro...