Anybody help me???

What is mean??

Fatal error: Uncaught exception 'Zend_Db_Adapter_Oracle_Exception' with message '12154 ORA-12154: TNS:could not resolve the connect identifier specified *' in /var/www/html/sgrh/library/Zend/Db/Adapter/Oracle.php:122 Stack trace: #0 /var/www/html/sgrh/library/Zend/Db/Adapter/Abstract.php(743): Zend_Db_Adapter_Oracle->_connect() #1


I don't know... please, help me!!!

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