Ora-12154 TNS: unable to process service name

Sometimes how to configure tnsnames. ora has a ora-12154
TNS: failed to handle service name errors! In fact, the configuration strings vary according to the Oracle version. For example, the content of the sqlnet. ora file of oracle8.1.5 is as follows: Path: orant \ net80 \ admin \ sqlnet. oratrace_level_client
= Off
# Sqlnet. authentication_services = (none)
Names. directory_path =
(Tnsnames, hostname)
Names. default_domain = World
Name. default_zone =
World
Automatic_ipc = off so. world must be added after the service name, for example: card. World =
(Description
=
(Address = (Protocol = TCP) (host = 192.168.0.2) (Port = 1521 ))

(CONNECT_DATA = (SID = card ))
)
However, in Oracle9i, the following configuration is required: Card =

(Description =
(Address_list =
(Address = (Protocol = TCP) (host =
192.168.0.2) (Port = 1521 ))
)
(CONNECT_DATA =
(Server = dedicated)

(SERVICE_NAME = card)
)

) Sqlnet. ora of oracle9i is like this: Path: oracle \ ora92 \ Network \ admin \ sqlnet. ora #
Sqlnet. ora network configuration file: C: \ oracle \ ora92 \ Network \ admin \ sqlnet. ora

# Generated by Oracle configuration tools. sqlnet. authentication_services =
(CNT) names. directory_path = (tnsnames, onames,
Hostname) so if you follow the oarcle8.1.5 configuration reference Oracle9i configuration, it is obviously incorrect. Because the sqlnet. ora file in oracle8.1.5 defines that the service name must have. World According to the Oracle version,
The SID may be changed to SERVICE_NAME.
Refer to global_name. Of listener. ora. In sqlnet. ora, set names. default_domain to null characters. It should be okay to exclude these issues.