mysql优化器总是选择错误的索引

tei_2000

yulihua49 发表于 2014-7-25 15:47
MYSQL 怎样使用这个hint？
能具体给个例句吗？
多谢了，我也需要这个。

你是问的这个意思吗？
explain select t.topic_id, t.topic_title, t.create_time from grp_topic as t force index(create_time) left join grp_group as g ON t.group_id = g.group_id where (g.city_id = 0 or g.city_id = 1) and t.is_del = 0 order by t.create_time desc limit 10;