Setting the Connection Character Set

The database character set determines the encoding of CHAR and VARCHAR2 character data types. The connection character set is used to describe the encoding of the incoming and outgoing application data, so that TimesTen can perform the necessary character set conversion between the application and the database.

For example, a non-Unicode application can communicate with a Unicode (AL32UTF8) database.

The ConnectionCharacterSet general connection attribute sets the character encoding for the connection, which can be different than the database character set. The connection uses the connection character set for information that passes through the connection, such as parameters, SQL query text, results and error messages. Choose a connection character set that matches the application environment or the character set of your data source.

Best performance results when the connection character set and the database character set are the same because no conversion occurs. When the connection character set and the database character set are different, data conversion is performed in the ODBC layer. Characters that cannot be converted to the target character set are changed to replacement characters.

The default connection character set is US7ASCII. This setting applies to both direct and client connections.