問題：現有如下數據表，用戶表： Members(QQnumber,userid); 充值表： Payment(payid,userid,paytime,amount); 查詢2012年各個月充值最多的用戶的qqnumber,要求根據qqnumber進行匯總（提示：一個qqnumber可能會有多個游戲角色數據，多條充值記錄;paytime為充值時間,），請寫出SQL語句。創建的表如下。Members表
Payment表
查詢語句如下：方法一：SELECT MAX( amount ) , t.qqnumber, t.MONTH FROM (SELECT MONTH( a.paytime ) MONTH , b.qqnumber, SUM( a.amount ) amount FROM payment a, members bWHERE a.userid = b.userid AND YEAR( a.paytime ) = '2016' GROUP BY b.qqnumber, MONTH ) AS t GROUP BY t.MONTH;方法二：SELECT MAX( amount ) , t.qqnumber, t.month FROM (SELECT MONTH( p.paytime ) AS MONTH , SUM( p.amount ) AS amount, m.qqnumber AS qqnumberFROM Members m JOIN Payment p ON m.userid = p.useridWHERE YEAR( p.paytime ) =2016 GROUP BY m.qqnumber, MONTH) AS t GROUP BY t.month;新聞熱點
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