PHP and SQL update table by specified row - php

Question

I have a table pulling info from a database with the last column of each row being an input tag labeled COMPLETE a user can click on. I want to be able to click on the tag and have it update my database to change a boolean field which would change COMPLETE from 0 to 1. Right now, I can't seem to update the rows if I click on them out of order. so If i click to update the first row and then click a few rows below, it will update the second row. It will update any row you want if you click the button for that row twice, but first it updates the row where you left off previously...
<form action='' method='POST'>
<?php
$current_date = date("Y-m-d");
$n = 1;
$sql = "SELECT id, date, pname, details, time, tech FROM task WHERE task='LAB' AND complete=0 ORDER BY date DESC";
$result = $link->query($sql);
echo $current_date;
echo "<table>
<tr>
<th>Date</th>
<th>Project</th>
<th>Details</th>
<th>Start Time</th>
<th>Technician</th>
</tr>";
while ($row = $result->fetch_assoc()) {
echo "<tr align='center'><td>" .$row["date"]. "</td><td>" .$row["pname"]. "</td><td>"
.$row["details"]. "</td><td>" .$row["time"]. "</td><td>" .$row["tech"]. "</td>
<td><input type='submit' name=".$n." value='Complete' /></td></tr>";
if (isset($_POST[$n])) {
$id = $row["id"];
$update = "UPDATE task SET complete = 1 WHERE task='LAB' AND id = ".$id."";
echo $update;
$update_result = $link->query($update);
}
$n++;
}
echo "</table>";
$link->close();
?>
</form>

Answer 1

One of the things I noticed was you don't do proper concatenation.
ANSWER:
You can try putting form for each row, then use hidden input field for storing the id:
while ($row = $result->fetch_assoc()) {
echo '<tr align="center">
<td>'.$row["date"].'</td>
<td>'.$row["pname"].'</td>
<td>'.$row["details"].'</td>
<td>'.$row["time"].'</td>
<td>'.$row["tech"].'</td>
<td>
<form action="" method="POST">
<input type="hidden" name="id" value="'.$row["id"].'">
<input type="submit" name="complete" value="Complete"/>
</form>
</td>
</tr>';
}
You can then process the form:
if(isset($_POST["complete"])) {
$id = $_POST["id"];
$stmt = $link->prepare("UPDATE task SET complete = 1 WHERE task='LAB' AND id = ?");
$stmt->bind_param("i", $id);
$stmt->execute();
$stmt->close();
}
Second Option:
You can try using Ajax for seamless transaction:
while ($row = $result->fetch_assoc()) {
echo '<tr align="center">
<td>'.$row["date"].'</td>
<td>'.$row["pname"].'</td>
<td>'.$row["details"].'</td>
<td>'.$row["time"].'</td>
<td>'.$row["tech"].'</td>
<td>
Complete
</td>
</tr>';
}
Then create your script (I'll be using jQuery for this example). You may include this at the bottom of your main file:
<script>
$(document).ready(function(){ /* PREPARE THE SCRIPT */
$(".btn").click(function(){ /* WHEN COMPLETE BUTTON IS CLICKED */
var elem = $(this),
id = elem.attr('data-artid'); /* GET THE ID OF THE CLICKED ELEMENT */
$.ajax({ /* PROCESS AJAX */
url: "process.php", /* THE FILE WHERE THE FORM WILL BE PROCESSED */
type: "POST", /* METHOD TO BE USED */
data: {"id":id}, /* THE DATA TO BE PASSED TO process.php */
dataType: 'json', /* TYPE OF DATA TO BE RETURNED */
success: function(result){ /* IF process.php IS SUCCESSFUL */
if(result.boolean){
elem.closest('tr').remove(); /* REMOVE THE ENTIRE ROW */
}
}
});
return false; /* THIS WILL PREVENT FROM SCROLLING TO THE TOP OF THE PAGE */
});
});
</script>
Then process the form in process.php (separate file):
/** INCLUDE HERE SOMEWHERE YOUR DATABASE CONNECTION **/
$boolean = false; /** DEFAULT VALUE TO BE RETURNED **/
if(!empty($_POST["id"])){
$id = $_POST["id"];
$stmt = $link->prepare("UPDATE task SET complete = 1 WHERE task='LAB' AND id = ?");
$stmt->bind_param("i", $id);
$stmt->execute();
$stmt->close();
$boolean = true;
}
echo json_encode(array('boolean' => $boolean)); /* THIS WILL BE RETURNED TO THE AJAX REQUEST */