When connected to a Unicode database, the Progress OpenEdge Wire Protocol driver supports the Unicode data types listed in the following table, in addition to standard ODBC data types listed in Data Types. The Use Wide Character Types connection string option must be enabled.

Progress OpenEdge Data Type Mapped to. . .
Char SQL_WCHAR
Varchar SQL_WVARCHAR

The driver supports the Unicode ODBC W (Wide) function calls, such as SQLConnectW. This allows the Driver Manager to transmit these calls directly to the driver. Otherwise, the Driver Manager would incur the additional overhead of converting the W calls to ANSI function calls, and vice versa.

See UTF-16 Applications on UNIX and Linux for related details.

Also, refer to Internationalization, localization, and Unicode in the Progress DataDirect for ODBC Drivers Reference for a more detailed explanation of Unicode.