Uncaught exception thrown in shutdown function.

Drupal\Core\Database\DatabaseExceptionWrapper: SQLSTATE[HY000]: General error: 2014 Cannot execute queries while other unbuffered queries are active. Consider using PDOStatement::fetchAll(). Alternatively, if your code is only ever going to run against mysql, you may enable query buffering by setting the PDO::MYSQL_ATTR_USE_BUFFERED_QUERY attribute.: DELETE FROM {semaphore} WHERE value = :db_condition_placeholder_0; Array ( [:db_condition_placeholder_0] => 21386219436419e5360c46e5.20205992 ) in _drupal_shutdown_function() (line 1068 of /var/www/html/egnatia2/core/includes/bootstrap.inc).

_drupal_shutdown_function()