select *
from wh_out,wh_outdl
where wh_out.outwhid = wh_outdl.outwhid and
wh_out.outwhid = 'PIT20090329-00032'select *
from wh_out,wh_outdl
where wh_out.outwhid = 'PIT20090329-00032' and
wh_outdl.outwhid = 'PIT20090329-00032' 以上两个SQL查询语句 那一种更有效率呢?
from wh_out,wh_outdl
where wh_out.outwhid = wh_outdl.outwhid and
wh_out.outwhid = 'PIT20090329-00032'select *
from wh_out,wh_outdl
where wh_out.outwhid = 'PIT20090329-00032' and
wh_outdl.outwhid = 'PIT20090329-00032' 以上两个SQL查询语句 那一种更有效率呢?
解决方案 »
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