I also had the same problem. It was due to the permission issue in wordpress directory. Navigate to the Directory where you have installed WordPress and…. run the following in your terminal: sudo chown www-data:www-data * -R sudo usermod -a -G www-data username Replace username with the username you are using like root.
As explained in my comment in the Question, the error is certainly in how the DROP TABLE is being performed. But answering to How does uninstalling WordPress plugins work?: If we do a register_uninstall_hook in our plugin, the callback is stored in the option uninstall_plugins in /wp-includes/plugin.php. $uninstallable_plugins[plugin_basename($file)] = $callback; update_option(‘uninstall_plugins’, $uninstallable_plugins); In the PHPDoc … Read more
In another answer I wrote about uninstall/activate/deactivate/upgrade routines. I guess most of the comments already tell it, but to sum it up: Uninstall: Remove everything, your plugin added Deactivate: Do nothing Activate: Do what your plugin needs. On Uninstall the user simply wants to get rid of the plugin, so it’s fair to not leave … Read more
As the other answers seem to imply, there is no built-in way to do this. There is no theme uninstall API similar to that for plugins. There is actually a long-standing ticket to get this feature added to WordPress core, so that themes can uninstall themselves. The consensus from the lead developers there seems to … Read more
How about something similar to this: function wpse65611_script() { wp_enqueue_style( ‘wp-pointer’ ); wp_enqueue_script( ‘wp-pointer’ ); wp_enqueue_script( ‘utils’ ); // for user settings ?> <script type=”text/javascript”> jQuery(‘#embed-github-gist .delete a’).click(function(){ jQuery(‘#embed-github-gist .delete a’).pointer({ content: ‘<h3>Delete this or delete everything?</h3><p><a id=”this” class=”primary button” href=”https://wordpress.stackexchange.com/questions/65611/url1″>Delete data</a> <a id=”everything” class=”button” href=”‘+jQuery(‘#embed-github-gist .delete a’).attr(‘href’)+'”>Delete plugin</a></p>’, position: { my: ‘left top’, at: … Read more
You could always use an uninstall.php file for the plugin instead. http://codex.wordpress.org/Function_Reference/register_uninstall_hook If the plugin can not be written without running code within the plugin, then the plugin should create a file named ‘uninstall.php’ in the base plugin folder. This file will be called, if it exists, during the uninstall process bypassing the uninstall hook. … Read more
It’s always advised to use $wpdb->prepare when you are taking input from user. This will help in protecting queries against SQL Injection. For more details, check the Codex When you use $wpdb->prepare, you must pass the variables to the query. In your case, you can skip using $wpdb->prepare as you are using a hard coded … Read more
Short answer: Plugins do not modify existing files, they hook into WordPress via an exposed API. Plugins can modify database schema. Plugins don’t have to uninstall cleanly. Plugin Hooks Plugins hook into WordPress at specific point exposed by the WordPress core. http://codex.wordpress.org/Plugin_API As an example, the function get_option() reads a site option from the database. … Read more
Using the uninstall hook would be legitimate if it worked, but it dumps the same error as the uninstall file. It would have more chances of working as it loads the main plugin file to perform the uninstall function, but if the taxonomy is not registered anymore (and it is not, as we need to … Read more
Replace “myplugin_” with your prefix: global $wpdb; $plugin_options = $wpdb->get_results( “SELECT option_name FROM $wpdb->options WHERE option_name LIKE ‘myplugin_%'” ); foreach( $plugin_options as $option ) { delete_option( $option->option_name ); }