Ubuntu

db = $db; } public function canLikelySetTransactionLevel() { $dbSettings = new Db\Settings(); return strtolower($dbSettings->getEngine()) === 'innodb'; } public function setUncommitted() { if ($this->db->supportsUncommitted === false) { // we know "Uncommitted" transaction level is not supported, we don't need to do anything as it won't work to set the status return false; } try { $backup = $this->db->fetchOne('SELECT @@TX_ISOLATION'); } catch (\Exception $e) { try { $backup = $this->db->fetchOne('SELECT @@transaction_isolation'); } catch (\Exception $e) { $this->db->supportsUncommitted = false; return false; } } try { $this->db->query('SET SESSION TRANSACTION ISOLATION LEVEL READ UNCOMMITTED'); $this->statusBackup = $backup; if ($this->db->supportsUncommitted === null) { // the first time we need to check if the transaction level actually works by // trying to set something w/ the new transaction isolation level Option::set(self::TEST_OPTION_NAME, '1'); } $this->db->supportsUncommitted = true; } catch (\Exception $e) { // setting the transaction level status did not work // catch eg 1665 Cannot execute statement: impossible to write to binary log since BINLOG_FORMAT = STATEMENT and at least one table uses a storage engine limited to row-based logging. InnoDB is limited to row-logging when transaction isolation level is READ COMMITTED or READ UNCOMMITTED $this->db->supportsUncommitted = false; $this->restorePreviousStatus(); return false; } return true; } public function restorePreviousStatus() { if ($this->statusBackup) { $value = strtoupper($this->statusBackup); $this->statusBackup = null; $value = str_replace('-', ' ', $value); if (in_array($value, array('REPEATABLE READ', 'READ COMMITTED', 'SERIALIZABLE'))) { $this->db->query('SET SESSION TRANSACTION ISOLATION LEVEL '.$value); } elseif ($value !== 'READ UNCOMMITTED') { $this->db->query('SET SESSION TRANSACTION ISOLATION LEVEL REPEATABLE READ'); } } } }