Connect the oracle 10g client to the oracle 9i Database

The oracle 10g client connects to the oracle 9i Database oracle10g client to connect to the oracle9i database. Net Manager Configuration profile: naming method: TNSNAMES service name: Create-next step to page 4th, select the SID (oracle8 or a lower version) and enter the database name, for example, ecoradb (the oracle9i database is used. Why do you choose this one? It cannot be said, but it is actually selected, if you do not select this, pl/SQL will report ORA-12154: TNS: unable to resolve the error of the specified connection identifier when connecting to the database) www.2cto.com originally tnsnames. ora format: 12.2.26.123 = (DESCRIPTION = (ADDRESS_LIST = (ADDRESS = (PROTOCOL = TCP) (HOST = 12.2.26.123) (PORT = 1521 ))) (CONNECT_DATA = (SERVICE_NAME = ecoradb) Final tnsnames. ora format: 12.2.26.123 = (DESCRIPTION = (ADDRESS_LIST = (ADDRESS = (PROTOCOL = TCP) (HOST = 12.2.26.123) (PORT = 1521 ))) (CONNECT_DATA = (SID = ecoradb) the difference is that service_name is changed to sid www.2cto.com. The complete configuration is as follows: SQL code # tnsnames. ora Network Configuration File: D: \ oracle \ product \ 10.2.0 \ client_1 \ NETWORK \ ADMIN \ tnsnames. ora # Generated by Oracle configuration tools. 12.2.26.123 = (DESCRIPTION = (ADDRESS_LIST = (ADDRESS = (PROTOCOL = TCP) (HOST = 12.2.26.123) (PORT = 1521) (CONNECT_DATA = (SID = ecoradb ))) www.2cto.com ECORADB = (DESCRIPTION = (ADDRESS_LIST = (ADDRESS = (PROTOCOL = TCP) (HOST = 12.2.26.123) (PORT = 1521) (CONNECT_DATA = (SID = ecoradb )))