Delete record on database through PHP button

Question

I'm trying to add a delete button on a table row, once the user clicks it, I want it to delete the record on the mysql database and therefore, not show on the table. My problem is when I click the delete button, I get a connection error! message, here's my php code:

<?php

        $id = $_GET['id'];


        $dbc = mysqli_connect('localhost','user','pass','db') or die('Connection error!');



        $query = "DELETE FROM table WHERE id = '$id'";
        mysqli_query($dbc, $query) or die('Database error!');
        \header('location:datapull.php');

    ?>

thanks for any help in advance...

Get the real error `or die(mysqli_error($dbc))` instead of `or die('Connection error!')` same thing for your query. Plus, is `table` your actual table name? I had to ask. Plus, get rid of the \ in `\header` — Funk Forty Niner, Apr 17 '15 at 02:05
Also at a minimum cast $id to an int. It's best to use prepared statements. http://stackoverflow.com/questions/60174/how-can-i-prevent-sql-injection-in-php?lq=1 — chris85, Apr 17 '15 at 02:09
Just so you know your script is vulnerable to SQL injection, anyone could pass `?id=' or '1'='1` to your script and delete every single row in that table. Use [mysqli_real_escape_string](http://php.net/manual/en/mysqli.real-escape-string.php) to sanitize your input. — Prime, Apr 17 '15 at 02:10
ok I switched it, now I get a blank page. My table name is not table, I just put it there for reference. i also got rid of the backslash. But all I get is a blank page — Ramses llorente, Apr 17 '15 at 02:10
Blank page means syntax errors. Add error reporting to the top of your file(s) right after your opening PHP tag for example ` — Funk Forty Niner, Apr 17 '15 at 02:12
Plus, what @AlphaDelta said to use `mysqli_real_escape_string()`. You may be trying to enter something that MySQL doesn't agree with. `or die(mysqli_error($dbc))` to `mysqli_query()` will tell you that. — Funk Forty Niner, Apr 17 '15 at 02:14
@Fred-ii- thats my whole php code, are you refering to where the begin button is located? — Ramses llorente, Apr 17 '15 at 02:17
Yes. If that is part of your PHP and in the same file. By the way, are you running this from your own computer or hosted site? If localhost; are you accessing via `http://localhost/file.php` or `file:///file.php`? — Funk Forty Niner, Apr 17 '15 at 02:18
@Fred-ii- I got these errors: Warning: mysqli_connect(): (28000/1045): Access denied for user 'admin'@'localhost' (using password: YES) in /home2/doctorc0/public_html/consultas/delete.php on line 9 Warning: mysqli_error() expects parameter 1 to be mysqli, boolean given in /home2/doctorc0/public_html/consultas/delete.php on line 9 — Ramses llorente, Apr 17 '15 at 02:18
`mysqli_error()` requires DB connection passed to it `mysqli_error($dbc)` — Funk Forty Niner, Apr 17 '15 at 02:19
`$dbc = mysqli_connect('localhost','user','pass','db') or die("Error " . mysqli_error($dbc));` and `mysqli_query($dbc, $query) or die(mysqli_error($dbc));` — Funk Forty Niner, Apr 17 '15 at 02:23
untill the connection is fixed you cant parse it on to the other functions — , Apr 17 '15 at 02:23
@Fred-ii- It's telling me I have denied access: Warning: mysqli_connect(): (28000/1045): Access denied for user 'user'@'localhost' (using password: YES) in /home2/doctorc0/public_html/consultas/delete.php on line 9 Warning: mysqli_error() expects parameter 1 to be mysqli, boolean given in /home2/doctorc0/public_html/consultas/delete.php on line 9 Error — Ramses llorente, Apr 17 '15 at 02:26
It's a permissions issue then. Check all credentials and that you chose the right database. Make sure you have `delete` rights also. You may not have that right to do it. — Funk Forty Niner, Apr 17 '15 at 02:27
@Fred-ii- Im so sorry, there was a letter missing, its going back to the datapull.php but its not deleting the row, I still see the info on it... — Ramses llorente, Apr 17 '15 at 02:30
I'd like to help further, but I really have to go to bed now; and my back's out. If nobody provides a solution, I'll come back to the question tomorrow. Good luck. — Funk Forty Niner, Apr 17 '15 at 02:31

score 0 · Accepted Answer · answered Apr 17 '15 at 02:25

0

Solution:

Step1. Over check: localhost,user,pass and db

Step2: Check privilege of user on your database.

If it does not work, I am over-sure that there is problem in your server. At that case contact with customer support of your server.

answered Apr 17 '15 at 02:25

Asif Iqbal

1,132
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@Dagon one of those *foot in the door* answers; just like the other one. – Funk Forty Niner Apr 17 '15 at 02:33
@dagon Im sorry if didnt respond, thanks for your help, Im still having issues, apparently the php code goes through because it redirects to the page but it doesnt delete the record on the database – Ramses llorente Apr 17 '15 at 02:35
Actually, I did not read all comments. I only read last comment " thanks a lot you guys, if anybody could help me further, it would be much appreciated". And I know this is the correct answer. – Asif Iqbal Apr 17 '15 at 02:36
@Dagon I got your back ^ – Funk Forty Niner Apr 17 '15 at 12:29

Mahendran Sakkarai · Answer 2 · 2015-04-17T03:22:34.953

-1

Double check your database username, password and database name.

Try this code and reply me with what you are getting.

$id = $_GET['id'];    
$dbc = mysqli_connect('localhost','user','pass','db') or die('Connection error!');
//Variables inside single quotes wont work. Change to this
$query = "DELETE FROM table WHERE id = '".$id."'";
mysqli_query($dbc, $query) or die('Database error!');
// Check how many rows is affected. If it is returns 0 it is not working. Else it will return how many rows is deleted.
printf("Records deleted: %d\n", mysqli_affected_rows($dbc)); 
exit;

edited Apr 17 '15 at 03:22

answered Apr 17 '15 at 02:53

Mahendran Sakkarai

8,381
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did you got `Records deleted:` with count of rows? – Mahendran Sakkarai Apr 17 '15 at 03:19
no, the page just loads the same. Nothing else to show – Ramses llorente Apr 17 '15 at 03:20
I updated the code. Check with that and use `exit`. So you can also able to view what is happening. – Mahendran Sakkarai Apr 17 '15 at 03:24
It doesn't do anything, it just tries to refresh the page and it stays the same. it won't print anything – Ramses llorente Apr 17 '15 at 03:30
I think you used the `header` before `exit` statement. Please comment the `header` statement or use `exit` before header and then check. `header` causes reloading. `exit` will terminate the execution of the script next to `exit` statement. So if you use `exit` before the `header` it wont let it to load the page. – Mahendran Sakkarai Apr 17 '15 at 03:35
Header has been commented but still does the same, I will link a pastebin of the code – Ramses llorente Apr 17 '15 at 03:38
I tried with my db. I'm getting this `Records deleted: 1`. So give the entire code which you are working with. – Mahendran Sakkarai Apr 17 '15 at 03:47
the php where the table is posted: [link](http://pastebin.com/5rUBUh5K) you have the delete.php – Ramses llorente Apr 17 '15 at 03:50
run the `delete.php` (which contains the delete code) with the id like `delete.php?id=10`. Instead of `10` use whatever id which you want to delete and then check whether you are getting `Records deleted:` and reply back. – Mahendran Sakkarai Apr 17 '15 at 04:24
perfect! it deleted one once I put an Id number, but how do I make it delete it without having to put it in? – Ramses llorente Apr 17 '15 at 04:37
I had to add an id number on the link and thats how it deleted it – Ramses llorente Apr 17 '15 at 04:41
You are using `$id = $_GET['id']` in your code. So, `$_GET['id']` will hold the value of attribute `id` in the `get method(appended in url)`. Check more about [get](http://php.net/manual/en/reserved.variables.get.php). If you think it solves the issue then accept the answer. – Mahendran Sakkarai Apr 17 '15 at 04:48

Delete record on database through PHP button

2 Answers2