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);哪位大神能解釋下，最后的where條件為什么加了能選出3個(gè)人的殺怪?jǐn)?shù)量，去掉就是有一個(gè)最大的。 user_idb,c兩個(gè)表不是一樣的嗎