Previously my all queries were running fine in CI version 2.0 but when I upgraded to 2.0.3 some of my SELECT queries were broken.
CI is adding
CI_DB_active_record::where() has a third param for escaping, this has worked better for me than switching on and off CI_DB_driver::_protect_identifiers
CI_DB_active_record::where()
CI_DB_driver::_protect_identifiers
public function where($key, $value = NULL, $escape = TRUE)
Not sure what CI version this was added in.
HTH someone