MySQL查询不选择不同

Question

我有这样的一个表：

Test_ID Question_ID User_ID 
--------------------------------- 
15   1   1 
15   2   1 
16   1   2 

而且我尝试去通过该表并打印出像这样为每个用户。 ：

测试ID：问题＃ 号码：使用此，我只能得到＃

进出口打印出测试ID。通过聚合函数

$result = mysqli_query($conn, "SELECT DISTINCT(Test_ID) AS Tcode, COUNT(Question_ID) AS Qcount,User_ID FROM user_answers WHERE User_ID = 1"); 

    while ($data = mysqli_fetch_array($result)) { 

     echo ''.$data['Tcode'].''; 
     echo ''.$data['Qcount'].''; 


    } 

Answer 1

使用组（并为此你don0t需要不同）

"SELECT Test_ID AS Tcode, COUNT(*) AS Qcount, User_ID 
     FROM user_answers 
     WHERE User_ID = 1 group by Tcode, User_ID ")