ORA-12504 TNS-12504 – TNS:listener was not given the SERVICE_NAME in CONNECT_DATA

This error occurs when there was no default service configured for the listener and SERVICE_NAME was missing from the request received by the listener. When a user tries to connect to the listener, it may be servicing several different databases. If user specifies a service name in the connect request then the listener will connect…

ORA-12502 TNS-12502 TNS:listener received no CONNECT_DATA from client

TNS:listener received no CONNECT_DATA from clientCause: No CONNECT_DATA was passed to the listener.Action: Check that the service name resolved from TNSNAMES.ORA has the CONNECT_DATA component of the connect descriptor. Below is the sample entry of tnsnames.ora:- #When using SERVICE_NAME in CONNECT_DATA componentorcl.example.com = (DESCRIPTION = (ADDRESS_LIST = (ADDRESS = (PROTOCOL = TCP)(HOST = myserver.example.com)(PORT =…