Conversion and Error Handling - ODBC Driver for Teradata

This section describes how ODBC Driver for Teradata:

Converts Parameter and Result set data to or from C data types to or from session character set

Converts SQL-Text to session character set

Handles conversion errors

Parameter and Result Set Data

Table 41 lists parameter and result set data.

Table 41: Parameter and Result Set Data 

	Session Character Set ASCII	Session Character Set Non-Unicode	Session Character Set Unicode
SQL_C_CHAR	No Conversion	No Conversion	Convert from Application Code Page to Unicode Note: See “Application Code Page” on page 124.
SQL_C_WCHAR	Convert from Application Code Page to Platform Unicode representation	Convert from Session Character Set to the Platform Unicode representation (UTF-8 on the UNIX OS, UTF-32 on Apple OS X, and UTF-16 on Windows)	No Conversion when session character set matches the Platform Unicode representation (UTF-8 on the UNIX OS, and UTF-16 on Windows. On Apple OS X, convert from session character set to UTF-32 Unicode representation.

Error Handling

Not all characters can be converted between Unicode and other non-Unicode code pages. Therefore, some characters are converted into error characters. For additional information on error characters, see Chapter 8 in International Character Set Support. In most cases, conversion errors result in the following Teradata Database errors:

6706 – The string contains an untranslatable character

6705 – An illegally formed character string was encountered during translation

In some cases, the “?” is used as the error character. In these cases, Teradata Database cannot detect conversion errors. Therefore, SQL-Text and character strings should match the session character set repertoire to avoid conversion errors.