Update several mysql entries at once from PHP table - php

Question

I have a table with some data from a mysql database. I need to update that information from within the table itself so when I press the button submit (table is inside a form) I need that all that data gets updated on the database. I can get the information from the database with no problem but I'm unable to update it! Here is the code:
<table border=1 cellpadding=4 cellspacing=0 width=960px style='font-size:10px'>
<form id='form1' name='form1' method='post' action='itself.php'>
<thead>
<tr>
<th colspan=3> People on the list </th>
<th><input type='submit' name='filtrar' id='filtrar' value='Filtrar'/></th>
<th><input type='submit' name='modificar' id='modificar' value='Modificar'/></th>
</tr>
<tr>
<th><label for='id'>ID</label></th>
<th><label for='id'>Friends</label></th>
<th><label for='id'>On the list?</label></th>
</tr>
<?
while($row = mysqli_fetch_array($result_listas, MYSQLI_BOTH))
$id= $row['id'];
{
?>
<tr>
<td><? echo "$row[id]" ?>
</td>
<td><select name='friends[<? echo "$id" ?>]' size='1' id='friends[<? echo "$id" ?>]'>
<option selected='selected'><? echo "$row[friends]" ?></option>
<option>less than 10</option>
<option>more than 10</option>
</select>
</td>
<td><select name='onlist[<? echo "$id" ?>]' size='1' id='onlist[<? echo "$id" ?>]'>
<option selected='selected'><? echo "$row[onlist]" ?></option>
<option>SI</option>
<option>NO</option>
</select>
</td>
<?
$ssql_min="select min(id) as id from listas_old";
$result_min= mysqli_query($link, $ssql_min);
$resultado_min = mysqli_fetch_array($result_min, MYSQLI_BOTH);
$ssql_max="select max(id) as id from listas_old";
$result_max= mysqli_query($link, $ssql_max);
$resultado_max = mysqli_fetch_array($result_max, MYSQLI_BOTH);
if(isset($_POST[modificar]))
{
for($i=$resultado_min['id']; $i<$resultado_max['id']; $i++)
{
$sql1="UPDATE listas_old SET friends='$friends[$i]', onlist='$onlist[$i]' WHERE id='$i'";
$result1=mysqli_query($link, $sql1);
}
}
?>

Answer 1

The OP wrote in a comment:
Got the solution for myself! This is what I did...
Change the for sentence like this:
for($i=$resultado_min['id'];
$i<=$resultado_max['id'];
$i++) {
$friendsfor= $_POST['friends('.$i.')'];
$onlistfor= $_POST['onlist('.$i.')'];
$sql1="UPDATE listas_old SET friends='$friendsfor', anotado= '$onlistfor' WHERE id='$i'";
}

Answer 2

It seems like you have your quotes all wrong in the update. You are trying to concatenate a string (your update sql) with php variables. But you need to make sure that php recognizes them as a variable instead of just as a string.
Should be like this
$sql1= "UPDATE listas_old SET friends='" . $friends[$i] . "', onlist='" . $onlist[$i] . "' WHERE id='" . $i . "'";
You only need to add in the single quotes if you are adding a varchar or date or something. If it is an int, you don't need the single quotes. Also I'm not sure what onlist would do, or if that is valid.