為什么要用c?
select a.user_name ,b.timestr,b.kills from user1 a? join user_kills b on a.id=b.user_id where b.kills =(select MAX (c.kill)from user_kills c where c.user_id=b.user_id);
其中c是哪個(gè)表?為什么要用c?
select a.user_name ,b.timestr,b.kills from user1 a? join user_kills b on a.id=b.user_id where b.kills =(select MAX (c.kill)from user_kills c where c.user_id=b.user_id);
其中c是哪個(gè)表?為什么要用c?
2016-05-06
舉報(bào)
2016-05-06
c 是select MAX(c.kill) from user_kills c where c.user_id = b.user_id 這部分sql語(yǔ)句的,使用c是因?yàn)槎鄰埍黻P(guān)聯(lián)查詢(xún)或者是有子查詢(xún)的時(shí)候使用別名便于區(qū)分