如何在mysql插入值中使用雙變量？

Question

我正在製作在線考試系統。但我面臨着一個問題。我的問題代碼在這裏。

<?php 
$sql="SELECT * FROM `question` WHERE sub_id=$subject_id"; 
$query=mysql_query($sql); 
$question_count=mysql_num_rows($query); 
for($a=1;$a<=$question_count;$a++){ 
    $ans{$a}=$_POST["ans$a"]; 
    $subject_id{$a}=$_POST["sub_id$a"]; 
    $group_id{$a}=$_POST["grup_id$a"]; 

    if(!mysql_query("INSERT INTO answer(sub_id,grup_id,ans)VALUES('$subject_id{$a}','$group_id{$a}','$ans{$a}')")){ 
     echo "problem of query<br>"; 
    } 

} 

?> 

我想用$ subject_id {$ A}，$ GROUP_ID {$ A} $ {答一$}在mysql中插入值。

請幫我用這些變量插入查詢

Answer 1

請修改方法爲VMAI至於你的問題你爲什麼不只是值到一個變量傳遞到像這樣的查詢之前存儲聲明：

$ans{$a}=$_POST["ans$a"]; 
$subject_id{$a}=$_POST["sub_id$a"]; 
$group_id{$a}=$_POST["grup_id$a"]; 

$_ans = $ans{$a}; 
$_subject_id = $subject_id{$a}; 
$_group_id = $group_id{$a}; 

if(!mysql_query("INSERT INTO answer(sub_id,grup_id,ans)VALUES('$_subject_id','$_group_id','$_ans')")){ 
    echo "problem of query<br>"; 
}