Oracle Database supports environments in which clients, Oracle Database servers, and non-Oracle Database servers use different character sets.
NCHAR support is provided for heterogeneous environments. You can set a variety of National Language Support (NLS) and Heterogeneous Services (HS) environment variables and initialization parameters to control data conversion between different character sets.
Character settings are defined by the following NLS and HS parameters:
Not Heterogeneous Distributed
|Oracle Database server|
||Heterogeneous Distributed||Non-Oracle Database server
||Heterogeneous Distributed||Oracle Database server
Oracle Database Globalization Support Guide for information about NLS parameters
Oracle Database Heterogeneous Connectivity Administrator's Guide for information about HS parameters
In a client/server environment, set the client character set to be the same as or a subset of the Oracle Database server character set, as illustrated in Figure 29-6.
In a non-heterogeneous environment, the client and server character sets should be either the same as or subsets of the main server character set, as illustrated in Figure 29-7:
In a heterogeneous environment, the globalization support parameter settings of the client, the transparent gateway, and the non-Oracle Database data source should be either the same or a subset of the database server character set as illustrated in Figure 29-8. Transparent gateways have full globalization support.
In a heterogeneous environment, only transparent gateways built with HS technology support complete
NCHAR capabilities. Whether a specific transparent gateway supports
NCHAR depends on the non-Oracle Database data source it is targeting. For information on how a particular transparent gateway handles
NCHAR support, consult the system-specific transparent gateway documentation.
See Also:Oracle Database Heterogeneous Connectivity Administrator's Guide for more detailed information about Heterogeneous Services