Wordpress wpdb->delete issue

3

I'm trying to delete a record from the database programmatically. When I have it hardcoded like this it does delete a record from the database:

$wpdb->delete( $table_name, array( 'user_id' => 1, 'timeMin' => 10), array('%d', '%d') );

However, when I try to do it in a dynamic manner with variables, it doesn't work. I even tried casting the variables to int to make sure they are they right type.

$id = (int) wp_get_current_user()->ID;
$time = (int) $_POST['umjp_time'];

$wpdb->delete( $table_name, array( 'user_id' => $id, 'timeMin' => $time), array('%d','%d'));

Why doesn't the dynamic code using variables work and how do I fix this?

phpwordpress

Share

Follow

asked May 16, 2018 at 12:27

Willem van der Veen

27.8k1515 gold badges162162 silver badges139139 bronze badges

• 1
  why not just use $wpdb->query($wpdb->prepare())? 

  – treyBake

   May 16, 2018 at 12:30
• 1
  I'll try, I thought this was the recommended way but it's not working 

  – Willem van der Veen

   May 16, 2018 at 12:31
•  
  with Wordpress I find that their standards/best practices are to avoid haha 

  – treyBake

   May 16, 2018 at 13:17
•  
  First: do use $wpdb->delete. It handles a lot of the prepare, etc. behind the scenes. Second: what do you get when you var_dump($id)? or var_dump($time)? The problem is almost certainly related to the values in those variables. 

  – random_user_name

   May 16, 2018 at 13:22

Add a comment

3 Answers

Sorted by:Reset to default

                                              Highest score (default)                                                                   Trending (recent votes count more)                                                                   Date modified (newest first)                                                                   Date created (oldest first)                              

1

I tried like this and it's working for me.

global $wpdb;

$id = (int) wp_get_current_user()->ID;
$time = (int) '4';
$table_name = 'testtable';
$wpdb->show_errors(); 
$wpdb->delete( $table_name, array( 'user_id' => $id, 'timeMin' => $time), array('%d','%d'));
$wpdb->print_error();

What errors you are getting please can you explain? You can print errors by using show_errors() and print_error() methods.

Share

Follow

answered May 16, 2018 at 13:22

Ankit Panchal

14944 bronze badges

• 1
  This is probably the most correct solution. Those using DELETE FROM will work, but that isn't how wpdb is intended to work. A little explanation would work - the critical piece being the user of array('%d') which converts the integer appropriately. 

  – Brian C

   Jul 14, 2021 at 12:27

Add a comment

 

2

 

this is how I would recommend doing it:

function vendor_module_remove_dealer($data)
{
    global $wpdb;

    $sql = 'DELETE FROM `'. $wpdb->prefix .'my_table` WHERE `primary_id` = %d;';

    try {
        $wpdb->query($wpdb->prepare($sql, array($data['primary-id'])));

        return true;
    } catch (Exception $e) {
        return 'Error! '. $wpdb->last_error;
    }
}

this will prevent SQL Injection and delete your record safely, if it fails an error msg will be returned :)

Share

Follow

answered May 16, 2018 at 13:18

treyBake

6,28766 gold badges2525 silver badges5454 bronze badges

Add a comment

-2

Please use below code i think it will work.

global $wpdb;

$id = (int) wp_get_current_user()->ID;
$time = (int) $_POST['umjp_time'];

$table_name = $wpdb->prefix . 'table_name';
if (!empty($id)) 
{

  $wpdb->query($wpdb->prepare("DELETE FROM $table_name WHERE user_id IN($id)"));

}

Share

Follow

edited May 16, 2018 at 13:29

 

answered May 16, 2018 at 13:10

raju_odi

1,3811212 silver badges2727 bronze badges

• 1
  this is open to SQL Injection :) should use the prepare method 

  – treyBake

   May 16, 2018 at 13:17
•  
  Code-only answers are not useful. Why does this work, where OP's code doesn't? Further, this is wide open to SQL injection. Don't post answers that are open to this sort of security attack. 

  – random_user_name

   May 16, 2018 at 13:21
•  
  sorry for missing $wpdb->prepare but now i had added. 

  – raju_odi

   May 16, 2018 at 13:32
• 1
  @raju_eww it's still open to SQL injection :) 

  – treyBake

   May 16, 2018 at 13:33
• 1
  You need to look into how to use $wpdb->prepare. It's not being used properly in your code. 

  – random_user_name

   May 16, 2018 at 13:47