求助 oracle 优化语句
这个语句要2秒多
select t1.isncode ,
t2.pinbancode ,
t1.outercode
from tblisnstatus t1 left join tblmoserialno t2
on t1.isncode=t2.moserialno where t1.isncode='021JHRHVH4000623'
同样一个语句,只是把查询的一个字段去掉,就只要0.0几秒。怎么优化上面的语句??
select t1.isncode ,
--t2.pinbancode ,
t1.outercode
from tblisnstatus t1 left join tblmoserialno t2
on t1.isncode=t2.moserialno where t1.isncode='021JHRHVH4000623'