Creating a Data Source

When a client application tries to establish a connection with a server, it typically provides a data source name (also known as a “DSN”). The driver manager looks through the ODBC configuration database for a data source whose name matches the DSN provided by the application.

On a Linux or Unix host, data sources are defined in a file; that file is usually named /etc/odbc.ini, but the name (and location) may vary. Use the following command to find out where unixODBC is searching for data source definitions:

$ odbc_config --odbcini --odbcinstini

On a Windows host, data sources are typically defined in the Windows registry.

You can also store a data source definition (called a “File DSN”) in a plain-text file of your choice. A typical data source definition for the EDB-ODBC driver looks like this:

$ cat /etc/odbc.ini
[EnterpriseDB]
Description = EnterpriseDB DSN
Driver = EnterpriseDB
Trace = yes
TraceFile = /tmp/odbc.log
Database = edb
Servername = localhost
UserName = enterprisedb
Password = manager
Port = 5444

The first line in the data source is the data source name. The name is a unique identifier, enclosed in square brackets. The data source name is followed by a series of 'keyword=value' pairs that identify individual connection properties that make up the data source.

The ODBC administrator utility creates named data sources for ODBC connections. In most cases, an ODBC administrator utility is distributed with the operating system (if you’re using Windows or unixODBC, the tool is called the ODBC Data Source Administrator). If your operating system doesn’t include an ODBC administrator, third-party options are available online.

Sections Adding a Data Source Definition in Windows and Adding a Data Source Definition in Linux walk you through adding a data source in Windows and Linux using the graphical tools available for each operating system. During the process of defining a data source, you’ll be asked to specify a set of connection properties. Section EDB-ODBC Connection Properties contains information about optional data source connection properties; you can specify connection properties with graphical tools or edit the odbc.ini file with a text editor.