的MySQL得到表中的數據沒有重複

Question

可能重複：
Mysql DISTINCT not working if I add another column

mysql> select DISTINCT number, id from table order by rand() 

+------+------------+ 
| id | number  | 
+------+------------+ 
| 2 | 4   | 
| 1 | 3   | 
| 4 | 3   | 
| 3 | 4   | 
+------+------------+ 

我需要類似的東西

+------+------------+ 
| id | number  | 
+------+------------+ 
| 2 | 4   | 
| 4 | 3   | 
+------+------------+ 

刷新

+------+------------+ 
| id | number  | 
+------+------------+ 
| 3 | 4   | 
| 1 | 3   | 
+------+------------+ 

刷新....

Answer 1

SELECT 
    (SELECT tt.id 
     FROM tableX AS tt 
     WHERE tt.number = t.number 
     ORDER BY RAND() 
      LIMIT 1 
    ) AS id, 
    number 
FROM 
    tableX AS t 
GROUP BY 
    number ;