不要显示重复的结果

时间:2014-03-19 18:09:34

标签: php mysql mysqli

这是我的表寄存器:

id  name         student_id  date     presence  absence_note    Tusername
50  hassimkhan    1112815    2014-03-08 P                        saahir
56  Karishma kods 1119112   2014-03-08  P                        saahir
58  Karishma kods 1119112   2014-03-09  P                        saahir           
60  hassimkhan    1112815   2014-03-09  A                        saahir

这是我的循环显示结果:

$retrieve = mysql_query("SELECT DISTINCT(student_id),presence FROM register"); 
    while($row = mysql_fetch_array($retrieve))          
        {
             echo $row['student_id'];
                }

我知道例如 id 56和58与student_id:1112815记录在某种程度上是不同的,但我想只显示一次,例如这些数据的结果:

1112815
1119112 

任何帮助?

2 个答案:

答案 0 :(得分:1)

请尝试GROUP

SELECT student_id, presence FROM register GROUP BY student_id

(未测试的)

答案 1 :(得分:0)

retrieve = mysql_query("SELECT student_id,presence FROM register GROUP BY student_id"); 
while($row = mysql_fetch_array($retrieve))          
{
  echo $row['student_id'];
}