Configuration Through the System Information (odbc.ini) File

To configure a data source manually, you edit the odbc.ini file with a text editor. The content of this file is divided into three sections.

At the beginning of the file is a section named [ODBC Data Sources] containing data_source_name=installed-driver pairs, for example:

The driver uses this section to match a data source to the appropriate installed driver.

The [ODBC Data Sources] section also includes data source definitions. The default odbc.ini contains a data source definition for each driver. Each data source definition begins with a data source name in square brackets, for example, [Oracle Wire Protocol 2]. The data source definitions contain connection string attribute=value pairs with default values. You can modify these values as appropriate for your system. Descriptions of these attributes are in each individual driver chapter. See Sample Default odbc.ini File for sample data sources.

The second section of the file is named [ODBC File DSN] and includes one keyword:

This keyword defines the path of the default location for file data sources (see File Data Sources).

Note: This section is not included in the default odbc.ini file that is installed by the product installer. You can add this section manually or, if you are using the Linux ODBC Administrator, it will be added automatically when you click Set Directory on the File DSN tab (see Configuration Through the Administrator under Configuration Through the Administrator).

The third section of the file is named [ODBC] and includes several keywords, for example:

[ODBC]
IANAAppCodePage=4
InstallDir=/opt/odbc
Trace=0
TraceFile=odbctrace.out
TraceDll=/opt/odbc/lib/ivtrc27.so
ODBCTraceMaxFileSize=102400
ODBCTraceMaxNumFiles=10

The IANAAppCodePage keyword defines the default value that all UNIX/Linux drivers use if individual data sources have not specified a different value. See the individual driver chapters and refer to "Code Page Values" in the DataDirect Connect Series for ODBC Reference for details. The default value is 4.

The InstallDir keyword must be included in this section. The value of this keyword is the path to the installation directory under which the /lib and /locale directories are contained. The installation process automatically writes your installation directory to the default odbc.ini file.

For example, if you choose an installation location of /opt/odbc, then the following line is written to the [ODBC] section of the default odbc.ini:

Note: If you are using only DSN-less connections through an odbcinst.ini file and do not have an odbc.ini file, then you must provide [ODBC] section information in the [ODBC] section of the odbcinst.ini file. The drivers and Driver Manager always check first in the [ODBC] section of an odbc.ini file. If no odbc.ini file exists or if the dbc.ini file does not contain an [ODBC] section, they check for an [ODBC] section in the odbcinst.ini file. See DSN-less Connections for details.

ODBC tracing allows you to trace calls to ODBC drivers and create a log of the traces for troubleshooting purposes. The following keywords all control tracing: Trace, TraceFile, TraceDLL, ODBCTraceMaxFileSize, and ODBCTraceMaxNumFiles.

For a complete description of these keywords and discussion of tracing, refer to "ODBC Trace" in the DataDirect Connect Series for ODBC Reference.