Overview of User and System DSNs

DSNs are resolved using a two-tiered naming system, where TimesTen first tries to resolve the DSN within the defined user DSNs and secondly within the defined system DSNs.

• A user DSN can be used only by the user who created the DSN.

  • On Windows, user DSNs are defined from the User DSN tab of the ODBC Data Source Administrator.

  • For TimesTen on Linux and UNIX, define user DSNs in the user odbc.ini file. TimesTen locates this file by first finding if a file is specified by the ODBCINI environment variable. If not, TimesTen locates the $HOME/.odbc.ini file.

    TimesTen supports data sources for both TimesTen Data Manager driver and the TimesTen Client driver in the .odbc.ini file.

  Although a user DSN is private to the user who created it, it is only the DSN, consisting of the character-string name and its attributes, that is private. The underlying database can be referenced by other users' user DSNs or by system DSNs.

• A system DSN can be used by any user on the system on which the system DSN is defined to connect to the TimesTen database.

  • On Windows, system DSNs are defined from the System DSN tab of the ODBC Data Source Administrator.

  • For TimesTen on Linux and UNIX, system DSNs are defined in the sys.odbc.ini file, which is referred to as the system odbc.ini file.

    TimesTen locates the system DSN file in the following order:

    • The file is located if it is specified by the SYSODBCINI environment variable.

    • In an installation, the file is located in timesten_home/conf/sys.odbc.ini.

    • If not found in any of these locations, TimesTen looks on the system for the /etc/odbc.ini file.