DB2 ODBC Unicode support

If your application manipulates UTF-8 data, set the initialization keyword CURRENTAPPENSCH to UNICODE or any Unicode CCSID value. When you set CURRENTAPPENSCH for Unicode data, you can use the following items for UTF-8 data:

• The generic APIs, such as SQLColumnPrivileges. When CURRENTAPPENSCH is set to UNICODE, these APIs accept UTF-8 string arguments and return all character string data in the result set in UTF-8.
• C data type SQL_C_CHAR. When CURRENTAPPENSCH is set to UNICODE, the DB2 for z/OS ODBC driver assumes UTF-8 data for SQL_C_CHAR. This data type is used by the APIs SQLBindCol(), SQLBindParameter(), and SQLGetData().

If your application manipulates UTF-16 data, use APIs with the suffix W, which are called wide APIs, on that data. Any generic API that accepts character string arguments has a wide API counterpart. For example, the corresponding wide API for the SQLConnect() API is SQLConnectW(). Wide APIs accept UTF-16 string arguments only. The initialization keyword CURRENTAPPENSCH does not affect these wide APIs. Regardless of what you specify for CURRENTAPPENSCH, these wide APIs always expect Unicode UTF-16 data. You can also use the SQL_C_WCHAR data type for UTF-16 data. Like wide APIs, SQL_C_WCHAR also assumes UTF-16 data, regardless of what you specify for CURRENTAPPENSCH.

You can use the SQLGetInfo() API with certain attributes, such as SQL_ASCII_SCCSID, to query the CCSID settings of the DB2 subsystem.