where b.user_id = c.user_id

Question

select a.user_name,b.timestr,b.kills from user1 as a left join user_kills as b on a.id = b.user_idwhere b.kills = (select max(c.kills) from user_kills as c where b.user_id = c.user_id);哪位大神能解释下，最后的where条件为什么加了能选出3个人的杀怪数量，去掉就是有一个最大的。 user_idb,c两个表不是一样的吗