WordPress at a glance
function is not described

wpdb::escape_by_ref() public WP 2.3.0

Escapes content by reference for insertion into the database, for security.

It's a method of the class: wpdb{}

No Hooks.

Return

Null. Nothing.

Usage

$wpdb = new wpdb();
$wpdb->escape_by_ref( $string );
$string(string) (required) (passed by reference — &)
String to escape.

Changelog

Since 2.3.0 Introduced.

Code of wpdb::escape_by_ref() WP 5.5.1

<?php
public function escape_by_ref( &$string ) {
	if ( ! is_float( $string ) ) {
		$string = $this->_real_escape( $string );
	}
}