/**
* Constructor
*
* @param array $tables Table names as keys, columns as value arrays
* @param string $from String to find, will be escaped.
* @param string $replacement String to use as replacement, will be escaped.
* @param wpdb $wpdb
*/
public function __construct(array $tables, $from, $replacement, wpdb $wpdb)
{
$this->tables = $tables;
$this->from = $wpdb->_real_escape($from);
$this->replacement = $wpdb->_real_escape($replacement);
$this->wpdb = $wpdb;
}