Character Sets

The CharSet connection property defines the character set that the driver uses to send character data to Adaptive Server, while the ClientCharset connection property defines the character set used by client applications.

The valid CharSet values are:

ServerDefault – when specified, Adaptive Server ODBC Driver communicates with Adaptive Server using the server's default character set. The Adaptive Server ODBC Driver converts character data for the client if the client and server use different character sets.
ClientDefault – when specified, Adaptive Server ODBC Driver communicates with Adaptive Server using the client-specified character set. In this case, if the default Adaptive Server character set is different from the client's, Adaptive Server converts character data to the client character set. Adaptive Server uses additional resources when performing character set conversions.
NoConversions – when specified, Adaptive Server ODBC Driver ignores the client's character set and does not convert character data. In this setting, the client application must ensure that character data is correctly converted between the client's character set and the default Adaptive Server character set. Use this value only under specific circumstances. For example, when character data stored in Adaptive Server must be converted in the client application using a customized character set conversion logic.

Note: In the Microsoft Windows ODBC Data Source Administrator, the Server Default, Client Charset, and No Conversions fields found in the Advanced window correspond to the CharSet values ServerDefault, ClientDefault, and NoConversions, respectively.

The Adaptive Server ODBC Driver determines the client character set, depending on the platform:

On Microsoft Windows, the default client character set selected is the ANSI code page for your login session. The valid code page types are ANSI, OEM, and Other. If Other is chosen, you must enter a valid Windows code page value.
By default, on UNIX, the Adaptive Server ODBC Driver examines the LC_CTYPE and LANG environment variables. If they are not set, the driver defaults to ISO 8859-1. If one of these environment variables are set, the driver looks for locales.dat in the $SYBASE/locales/locales.dat directory to pick up the corresponding Adaptive Server character set. If the file is not found, the driver looks into its own map in memory to lookup the corresponding Adaptive Server character set.