1万6千条数据left join 特别慢 求优化sql
Herbe 2015-10-30 01:16:09 现在有两张表大约都是1万6千条左右 2张表left join 执行后大约27秒很慢 求优化
select tt.id,tt.email,tt.mobilenum from (select t.id,t.email,t.mobilenum from tmp_table t) tt left join
(select u.id,u.email from hui_user u where u.meetid = 411) usr on tt.email = usr.email ;