Display saved checkbox value - php

Question

I have some checkbox options that I save in the DB. I was able to view and also select multiple options and save them in the DB. The issue is that I want to display the saved information but I don't know how to do that.
<form action="save_comp.php" method="post">
<?php
//Display
include ('mysql_connect.php');
$sql = mysql_query("SELECT * FROM competency ");
//$row = mysql_fetch_array($sql);
while($row = mysql_fetch_array($sql))
{
echo"<input type='checkbox' name='comp[]' value= ".$row['id']." /> ".$row['competency']." <br />";
}
?>
<input name="submit" type="submit" value="submit" />
</form>
Save into DB
<?php
session_start();
$id = $_SESSION['user_id'];
//$id = 3;
include ('mysql_connect.php');
$insStr = '';
foreach($_POST['comp'] as $val){ $insStr .=$val.","; }
mysql_query("INSERT INTO competency_result (user_id,result) VALUES ( '$id', '$insStr' )") or die(mysql_error());
echo'<script>alert("Inserted Successfully")</script>';
?>
All I want to do now is to display the saved information in a table format. I tried doing this but it only showed me the saved ID
<?php
$res= mysql_query("SELECT * FROM competency_result WHERE user_id = '$user'")or die(mysql_error());
while($row = mysql_fetch_array($res))
{
echo"<tr>";
echo"<td> $row[result]</td>";
?>
<?php
echo"</tr>";
}
?>

Answer 1

<form action="save_comp.php" method="post">
<?php
//Display
include ('mysql_connect.php');
$sql = mysql_query("SELECT * FROM competency ");
//$row = mysql_fetch_array($sql);
while($row = mysql_fetch_array($sql))
{
echo"<input type='checkbox' name='comp[". $row['id']. "]' value='". $row['competency'] ."' /> ".$row['competency']." <br />";
}
?>
<input name="submit" type="submit" value="submit" />
</form>

Answer 2

If you want to checkboxes check then you can try with below code:
<?php
$sql = mysql_query("SELECT name FROM competency ");
//$row = mysql_fetch_array($sql);
while($row = mysql_fetch_array($sql))
{
$focus=explode(",",$row['name']);
?>
<input type="checkbox" name="focus[]" value="Art" <?php if(in_array("Comp",$focus)) { ?> checked="checked" <?php } ?> >
<input type="checkbox" name="focus[]" value="Mathematics" <?php if(in_array("Mathematics",$focus)) { ?> checked="checked" <?php } ?> >
<input type="checkbox" name="focus[]" value="Dance" <?php if(in_array("Dance",$focus)) { ?> checked="checked" <?php } ?> >
<?php
}
?>