Where Data Sources Are Held

Data sources can be used on Windows or UNIX/Linux-based systems to help clients make it easier to make connections.

When you connect to a database using ODBC, you use an ODBC data source. The data source contains a set of connection parameters. You need an ODBC data source on the client computer for each database to which you connect.

If you have a data source, your connection string can simply name the data source to use:

Data source – Use the DSN connection parameter to reference a user or system data source:
```
DSN=my data source
```
On Windows, user and system data sources are stored in the registry and in the file odbc.ini. On UNIX platforms user data sources are in the file .odbc.ini.
File data source – Use the FileDSN connection parameter to reference a data source held in a file:
```
FileDSN=mysource.dsn
```

Except for encrypted passwords, which are allowed in FileDSNs only, you can put identical connection information in DSNs and FileDSNs.

ODBC data sources can be used to help a wide range of clients connect including:

Applications on Windows, Linux and Unix that use the ODBC interface
Java applications using the iAnywhere JDBC driver