diff --git a/src/wp-includes/media.php b/src/wp-includes/media.php
index 6a1bddbefc..506c86c5ee 100644
--- a/src/wp-includes/media.php
+++ b/src/wp-includes/media.php
@@ -3295,7 +3295,7 @@ function wp_maybe_generate_attachment_metadata( $attachment ) {
  * @global wpdb $wpdb WordPress database abstraction object.
  *
  * @param string $url The URL to resolve.
- * @return int The found post ID.
+ * @return int The found post ID, or 0 on failure.
  */
 function attachment_url_to_postid( $url ) {
 	global $wpdb;
@@ -3312,9 +3312,8 @@ function attachment_url_to_postid( $url ) {
 		$path
 	);
 	$post_id = $wpdb->get_var( $sql );
-	if ( ! empty( $post_id ) ) {
-		return (int) $post_id;
-	}
+
+	return (int) $post_id;
 }
 
 /**
diff --git a/tests/phpunit/tests/media.php b/tests/phpunit/tests/media.php
index f0960d7536..9f0a131503 100644
--- a/tests/phpunit/tests/media.php
+++ b/tests/phpunit/tests/media.php
@@ -501,6 +501,15 @@ VIDEO;
 		return $dir;
 	}
 
+	/**
+	 * @ticket 31044
+	 */
+	function test_attachment_url_to_postid_with_empty_url() {
+		$post_id = attachment_url_to_postid( '' );
+		$this->assertInternalType( 'int', $post_id );
+		$this->assertEquals( 0, $post_id );
+	}
+
 	function test_wp_check_filetype() {
 		$url = 'http://example.com/testFile.mp4?autoplay=true&otherstuff=false';
 		$filetype = wp_check_filetype( $url );