WordPress: Get post id by meta key and value

get_post_id_by_meta_key_and_value.php

<?php
if (!function_exists('get_post_id_by_meta_key_and_value')) {
	/**
	 * Get post id from meta key and value
	 * @param string $key
	 * @param mixed $value
	 * @return int|bool
	 * @author David M&aring;rtensson <david.martensson@gmail.com>
	 */
	function get_post_id_by_meta_key_and_value($key, $value) {
		global $wpdb;
		$meta = $wpdb->get_results("SELECT * FROM `".$wpdb->postmeta."` WHERE meta_key='".$wpdb->escape($key)."' AND meta_value='".$wpdb->escape($value)."'");
		if (is_array($meta) && !empty($meta) && isset($meta[0])) {
			$meta = $meta[0];
		}		
		if (is_object($meta)) {
			return $meta->post_id;
		}
		else {
			return false;
		}
	}
}

is this code get the ID is the last post when have more result?

Notice: wpdb::escape is deprecated since version 3.6! Use wpdb::prepare() or esc_sql() instead. in /Users/emmanouilgketsim/htdocs/svn/infosource.culturalcare.com/wp-includes/functions.php on line 3078

For WP version >= 3.6, use esc_sql() instead of $wpdb->escape and it should not throw any notice.

Thanks for it

For WP version >= 3.6 use in line 12
$meta = $wpdb->get_results( $wpdb->prepare( "SELECT * FROM ".$wpdb->postmeta." WHERE meta_key=%s AND meta_value=%s", $key, $value ) );