/**
* Execute a sql-multi-query.
*
* @param string $sql
*
* @return false|Result[] "Result"-Array by "<b>SELECT</b>"-queries<br />
* "boolean" by only "<b>INSERT</b>"-queries<br />
* "boolean" by only (affected_rows) by "<b>UPDATE / DELETE</b>"-queries<br />
* "boolean" by only by e.g. "DROP"-queries<br />
*
* @throws \Exception
*/
public function multi_query($sql)
{
if (!$this->isReady()) {
return false;
}
if (!$sql || $sql === '') {
$this->_debug->displayError('Can\'t execute an empty Query', false);
return false;
}
$query_start_time = microtime(true);
$resultTmp = \mysqli_multi_query($this->link, $sql);
$query_duration = microtime(true) - $query_start_time;
$this->_debug->logQuery($sql, $query_duration, 0);
$returnTheResult = false;
$result = array();
if ($resultTmp) {
do {
$resultTmpInner = \mysqli_store_result($this->link);
if ($resultTmpInner instanceof \mysqli_result) {
$returnTheResult = true;
$result[] = new Result($sql, $resultTmpInner);
} else {
$errorMsg = \mysqli_error($this->link);
// is the query successful
if ($resultTmpInner === true || !$errorMsg) {
$result[] = true;
} else {
$result[] = $this->queryErrorHandling($errorMsg, $sql);
}
}
} while (\mysqli_more_results($this->link) === true ? \mysqli_next_result($this->link) : false);
} else {
$errorMsg = \mysqli_error($this->link);
if ($this->_debug->checkForDev() === true) {
echo "Info: maybe you have to increase your 'max_allowed_packet = 30M' in the config: 'my.conf' \n<br />";
echo 'Error:' . $errorMsg;
}
$this->_debug->mailToAdmin('SQL-Error in mysqli_multi_query', $errorMsg . ":\n<br />" . $sql);
}
// return the result only if there was a "SELECT"-query
if ($returnTheResult === true) {
return $result;
}
if (!in_array(false, $result, true)) {
return true;
} else {
return false;
}
}
/**
* Error-handling for the sql-query.
*
* @param string $errorMsg
* @param string $sql
*
* @throws \Exception
*
* @return bool
*/
private function queryErrorHandling($errorMsg, $sql)
{
if ($errorMsg === 'DB server has gone away' || $errorMsg === 'MySQL server has gone away') {
static $reconnectCounter;
// exit if we have more then 3 "DB server has gone away"-errors
if ($reconnectCounter > 3) {
$this->_debug->mailToAdmin('SQL-Fatal-Error', $errorMsg . ":\n<br />" . $sql, 5);
throw new \Exception($errorMsg);
} else {
$this->_debug->mailToAdmin('SQL-Error', $errorMsg . ":\n<br />" . $sql);
// reconnect
$reconnectCounter++;
$this->_db->reconnect(true);
// re-run the current query
return $this->execute();
}
} else {
$this->_debug->mailToAdmin('SQL-Warning', $errorMsg . ":\n<br />" . $sql);
// this query returned an error, we must display it (only for dev) !!!
$this->_debug->displayError($errorMsg . ' | ' . $sql);
}
return false;
}