php foreach loop insert data feed back repeat everytime - php

Question

this is my php code. hire is a problem i use check box selection and insert data in my database. but it insert data by foreach loop. so when press ok if data successfully insert then for 3 selection it say
successfully register
successfully register
successfully register
but i want it say only once successfully register
<?php
$db=require "script_database/connect.php";
$query = "SELECT * FROM course";
$query1="select * from selection where student_id='1229CSE00241' and semester='FALL2015' ";
$key=mysql_query($query1);
if(mysql_num_rows($key)>0)
{
echo "you already selected courses for registration";
}
else if($_POST['buy']==''){
echo "<h2><center>You didn't select any courses</h2></center>";
}
else{
foreach($_POST['buy'] as $item) {
$query = "SELECT * FROM course WHERE id = $item
";
if ($r = mysql_query($query)) {
while ($row = mysql_fetch_array($r)) {
$student_id="1229CSE00241";
$id=$item;
$course_id=$row['course_id'];
$course_title=$row['course_title'];
$course_credits=$row['course_credits'];
$course_status=$row['course_status'];
$semester="FALL2015";
}
} else {
print '<p style="color: blue">Error!</p>';
}
{
$insert_query="insert into selection(student_id,semester,course_id,course_title,course_credits,course_status,date_time) values ('$student_id','$semester','$course_id','$course_title','$course_credits','$course_status',NOW())";
}
//here is my problem
//it repeat every time when insert data but i want to make it only once
if(mysql_query($insert_query))
{
echo "successfully register";
}
else
echo "problem show";
}
}?>

Answer 1

Before you start your foreach loop set a flag like:
$error = false;
Then in your loop
if(!mysql_query($insert_query))
{
$error =true;
}
And after the loop has closed
if($error){
echo "problem show";
}else{
echo "successfully register";
}