Update link for each table row - php

Question

With the code i have i can succesfully read and display data from my database,
"agencies_validation" does this. I also manage to make it so it display Update Link for each row. But the Update link doesen't work. So what i want it to do is when i click Update link it calls "agencies_admin_update.php" which is supposed to Update that row. But it doesn't work.
//agencies_validation
<table border="2">
<tr>
<td>title</td>
</tr>
<?php
include_once 'database.php';
echo '<form action= "agencies_admin_update.php" method="get">';
$valid_query = "SELECT * FROM agencies ";
$valid_result = mysqli_query($link, $valid_query);
while ($row = mysqli_fetch_array($valid_result)) {
echo '<tr>';
$id = $row['id'];
echo '<td>'.$row['title'].'</td>';
echo "<td><a href='agencies_admin_update.php?'>UPDATE</a></td>";
echo '<tr>';
}
echo '</form>';
?>
</table>
and
//agencies_admin_update.php
<?php
include_once 'database.php';
$id = $_GET['id'];
$query = "UPDATE agencies SET admin=2 WHERE id = $id";
header("Location: agencies_validation.php");
?>

Answer 1

The first you have to add the ID to link URL:
...
echo "<td><a href='agencies_admin_update.php?id=" . $id . "'>UPDATE</a></td>";
...
The second you must not only to generate the SQL query, but and execute it:
...
$query = "UPDATE agencies SET admin=2 WHERE id = $id";
mysqli_query($link, $query)
...

Answer 2

If this is really all code, then I think, you are just specifying your query in agencies_admin_update.php and not executing it.
See here:
$query = "UPDATE agencies SET admin=2 WHERE id = $id";
The $query variable is set, but not executed.
After specifying the variable you are redirecting the user immidiately with this code:
header("Location: agencies_validation.php");
But I'm wondering, how this should work, because you have no $id specified, which you want to update in agencies_admin_update.php.

Answer 3

Try this!!!
<td><a href='agencies_admin_update.php?id=<?php echo $row['id']; ?>'>UPDATE</a></td>

Answer 4

You need to execute the update query in the agencies_admin_update.php file and send id with the url in agencies_validation file
//agencies_validation
<table border="2">
<tr>
<td>title</td>
</tr>
<?php
include_once 'database.php';
echo '<form action= "agencies_admin_update.php" method="get">';
$valid_query = "SELECT * FROM agencies ";
$valid_result = mysqli_query($link, $valid_query);
while ($row = mysqli_fetch_array($valid_result)) {
echo '<tr>';
$id = $row['id'];
echo '<td>'.$row['title'].'</td>';
echo "<td><a href='agencies_admin_update.php?id=".$id."'>UPDATE</a></td>";
echo '<tr>';
}
echo '</form>';
?>
</table>
Execute query in this file
// agencies_validation
<?php
include_once 'database.php';
$id = $_GET['id'];
$query = "UPDATE agencies SET admin=2 WHERE id = $id";
$result = mysqli_query($link, $query);
if($result) {
// Show success message
header("Location: agencies_validation.php");
} else {
// Show error message
header("Location: agencies_validation.php");
}
?>