protected function _prepareQuery()
{
if (!($stmt = $this->mysqli()->prepare($this->_query))) {
$msg = $this->mysqli()->error . " query: " . $this->_query;
$num = $this->mysqli()->errno;
$this->reset();
throw new Exception($msg, $num);
}
if ($this->traceEnabled) {
$this->traceStartQ = microtime(true);
}
return $stmt;
}