wpdb::get_col() WordPress Method

	public function get_col( $query = null, $x = 0 ) {
		if ( $query ) {
			if ( $this->check_current_query && $this->check_safe_collation( $query ) ) {
				$this->check_current_query = false;
			}

			$this->query( $query );
		}

		$new_array = array();
		// Extract the column values.
		if ( $this->last_result ) {
			for ( $i = 0, $j = count( $this->last_result ); $i < $j; $i++ ) {
				$new_array[ $i ] = $this->get_var( null, $x, $i );
			}
		}
		return $new_array;
	}
Uses	Description
wp-includes/wp-db.php:wpdb::check_safe_collation()	Checks if the query is accessing a collation considered safe on the current version of MySQL.
wp-includes/wp-db.php:wpdb::query()	Performs a database query, using current database connection.
wp-includes/wp-db.php:wpdb::get_var()	Retrieves one variable from the database.
Used By	Description
wp-includes/comment.php:_wp_batch_update_comment_type()	Updates the comment type for a batch of comments.
wp-includes/ms-site.php:wp_delete_site()	Deletes a site from the database.
wp-includes/class-wp-network-query.php:WP_Network_Query::get_network_ids()	Used internally to get a list of network IDs matching the query vars.
wp-includes/class-wp-site-query.php:WP_Site_Query::get_site_ids()	Used internally to get a list of site IDs matching the query vars.
wp-includes/user.php:wp_get_users_with_no_role()	Gets the user IDs of all users with no role on this site.
wp-includes/class-wp-comment-query.php:WP_Comment_Query::get_comment_ids()	Used internally to get a list of comment IDs matching the query vars.
wp-admin/install-helper.php:maybe_drop_column()	Drops column from database table, if it exists.
wp-admin/includes/export.php:export_wp()	Generates the WXR export file for download.
wp-admin/includes/deprecated.php:WP_User_Search::query()	Executes the user search query.
wp-admin/includes/deprecated.php:get_author_user_ids()	Get all user IDs.
wp-admin/includes/deprecated.php:get_editable_user_ids()	Gets the IDs of any users who can edit posts.
wp-admin/includes/deprecated.php:get_nonauthor_user_ids()	Gets all users who are not authors.
wp-admin/includes/ms.php:wpmu_delete_user()	Delete a user from the network and remove from all sites.
wp-admin/includes/schema.php:populate_options()	Create WordPress options and set the default values.
wp-admin/includes/upgrade.php:maybe_create_table()	Creates a table in the database, if it doesn’t already exist.
wp-admin/includes/upgrade.php:maybe_add_column()	Adds column to a database table, if it doesn’t already exist.
wp-admin/includes/user.php:wp_delete_user()	Remove user and optionally reassign posts and links to another user.
wp-admin/includes/template.php:meta_form()	Prints the form in the Custom Fields meta box.
wp-admin/includes/class-wp-ms-sites-list-table.php:WP_MS_Sites_List_Table::prepare_items()	Prepares the list of sites for display.
wp-admin/includes/post.php:get_meta_keys()	Returns a list of previously defined keys.
wp-includes/post.php:get_available_post_mime_types()	Get all available post MIME types for a given post type.
wp-admin/includes/nav-menu.php:_wp_delete_orphaned_draft_menu_items()	Deletes orphaned draft menu items
wp-includes/deprecated.php:get_usermeta()	Retrieve user metadata.
wp-includes/class-wp-query.php:WP_Query::get_posts()	Retrieves an array of posts based on query variables.
wp-includes/functions.php:do_enclose()	Check content for video and audio links to add as enclosures.
wp-includes/taxonomy.php:wp_set_object_terms()	Creates term and taxonomy relationships.
wp-includes/taxonomy.php:wp_delete_term()	Removes a term from the database.
wp-includes/taxonomy.php:get_objects_in_term()	Retrieves object IDs of valid taxonomy and term.
wp-includes/class-wp-user-query.php:WP_User_Query::query()	Executes the query, with the current variables.
wp-includes/user.php:count_users()	Counts number of users who have each of the user roles.
wp-includes/post.php:wp_delete_auto_drafts()	Delete auto-drafts for new posts that are > 7 days old.
wp-includes/post.php:wp_delete_attachment()	Trash or delete an attachment.
wp-includes/post.php:get_all_page_ids()	Get a list of page IDs.
wp-includes/post.php:wp_delete_post()	Trash or delete a post or page.
wp-includes/ms-functions.php:remove_user_from_blog()	Removes a user from a blog.
wp-includes/author-template.php:is_multi_author()	Determines whether this site has more than one author.
wp-includes/comment.php:wp_delete_comment()	Trashes or deletes a comment.
wp-includes/meta.php:delete_metadata()	Deletes metadata for the specified object.
wp-includes/meta.php:update_metadata()	Updates metadata for the specified object. If no value already exists for the specified object ID and metadata key, the metadata will be added.