Fatal error: Uncaught Error: Call to a member function quote() on null in /var/www/dizy/vendor/magento/zendframework1/library/Zend/Db/Adapter/Pdo/Abstract.php:296 Stack trace: #0 /var/www/dizy/vendor/magento/zendframework1/library/Zend/Db/Adapter/Abstract.php(906): Zend_Db_Adapter_Pdo_Abstract->_quote('a') #1 /var/www/dizy/vendor/magento/zendframework1/library/Zend/Db/Statement.php(182): Zend_Db_Adapter_Abstract->quote('a') #2 /var/www/dizy/vendor/magento/zendframework1/library/Zend/Db/Statement.php(137): Zend_Db_Statement->_stripQuoted('SELECT DISTINCT...') #3 /var/www/dizy/vendor/magento/zendframework1/library/Zend/Db/Statement.php(114): Zend_Db_Statement->_parseParameters('SELECT DISTINCT...') #4 /var/www/dizy/vendor/magento/zendframework1/library/Zend/Db/Adapter/Pdo/Abstract.php(184): Zend_Db_Statement->__construct(Object(Magento\Framework\DB\Adapter\Pdo\Mysql\Interceptor), 'SELECT DISTINCT...') #5 /var/www/dizy/vendor/magento/zendframework1/library/Zend/Db/Adapter/Abstract.php(479): Zend_Db_Adapter_Pdo_Abstract->prep in /var/www/dizy/vendor/magento/zendframework1/library/Zend/Db/Adapter/Pdo/Abstract.php on line 296