如何獲取其他列具有最大值的行中列的值？

Question

我有一個表有三個字段user_name,page和n_loads。我想按user_name對錶格進行分組，對於每個用戶名，我想顯示最大負載數以及與此（最大）負載數對應的頁面。我可以在一個MySQL條款中做到嗎？

Answer 1

SELECT a.* 
FROM tableName a 
     INNER JOIN 
     (
      SELECT username, MAX(n_loads) n_loads 
      FROM tableName 
      GROUP BY username 
     ) b ON a.username = b.username AND 
       a.n_loads = b.n_loads 

或

SELECT a.* 
FROM tableName a 
WHERE n_loads = 
     (SELECT MAX(b.n_loads) 
     FROM tableName b 
     WHERE a.username = b.username); 

• SQLFiddle Demo (both query)