sqllite 判断 某个id是否存在于表中了,如果存在则不插入,不存在则插入 2015/11/22 36137 清华大佬耗费三个月吐血整理的几百G的资源,免费分享!....>>> INSERT INTO USER (email,ADDTIME) (SELECT 'email','addTime' FROM USER u2 JOIN( SELECT COUNT(*) num FROM USER u1 WHERE u1.id = 87) u3 ON u3.num < 1 LIMIT 1)