Definitions of ODBC.INI tags

The following table provides definitions of the ODBC.ini tags.

Table 1. Definitions of ODBC.ini tags
Tag Definition
Driver The data-source-specific library used by the Driver Manager.
Database name (mandatory) The name of the database used by the DSN.
PortNumber (mandatory) The Network Service number on which the database server is listening for connections.
HostName (mandatory) The name of the host machine on which the database is running.
LogonID The default user ID for logon to the database server.
Password The password for the default user ID.
APILevel A number indicating the ODBC interface conformance level supported by the driver:
  • 0 — None
  • 1 — Level 1 supported
  • 2 — Level 2 supported
ConnectFunctions A three-character string indicating whether the driver supports SQLConnect, SQLDriverConnect, and SQLBrowseConnect.
  • If the driver supports SQLConnect, the first character is "Y"; otherwise, it is "N".
  • If the driver supports SQLDriverConnect, the second character is "Y"; otherwise, it is "N".
  • If the driver supports SQLBrowseConnect, the third character is "Y"; otherwise, it is "N".
  • For example, if a driver supports SQLConnect and SQLDriverConnect but not SQLBrowseConnect, the three-character string is "YYN".
CPTimeout The time interval setting for Connection Pooling Timeout. Not supported for UNIX.
DriverODBCVer A character string with the version of ODBC that the driver supports. The version is of the form nn.nn, where the first two digits are the major version and the next two digits are the minor version.
FileUsage A number indicating how a file-based driver directly treats files in a data source:
  • 0 — The driver is not a file-based driver. For example, a driver may be a DBMS-based driver.
  • 1 — A file-based driver treats files in a data source as tables. For example, an Xbase driver treats each Xbase file as a table.
  • 2 — A file-based driver treats files in a data source as a catalog. For example, a Microsoft® Access driver treats each Microsoft Access file as a complete database.
SQLLevel A number indicating the SQL-92 grammar supported by the driver:
  • 0 — SQL-92 Entry
  • 1 — FIPS127-2 Transitional
  • 2 — SQL-92 Intermediate
  • 3 — SQL-92 Full
UsageCount Indicates driver libraries are in use. This value should not be modified.
ArraySize A hint that can be provided to the ODBC driver with regards to how many records can be retrieved from the server at a time.
DefaultLongDataBuffLen Controls the size of an LOB that can be accessed in SQL.
DefaultIsolationLevel (mandatory) The default isolation level under which data will be accessed.
StaticCursorLongColBuffLen The default size for retrieving sections of LVARBINARY data.

The DefaultLongDataBuffLen parameter controls the size of an LOB that can be accessed in SQL. It defaults to 2048 (2mb) and must be set to match the largest possible LOB used by the application. The parameter is set via the registry on Windows and the odbc.ini file on UNIX and is specific to a DSN.

The DefaultIsolationLevel setting requires careful consideration. A transaction's isolation level will influence the type of record locks that are applied to records read from the database. The default value for this setting is REPEATABLE READ, unless you specify another setting during configuration. This will instruct the server to apply record SHARE locks, at a minimum, for the duration of a transaction to records read from the database. For most query tools, it is appropriate to set a default level of READ COMMITTED. The default isolation level setting can and will be overridden by applications.

The ArraySize setting is a hint that can be provided to the ODBC driver with regards to how many records can be retrieved from the server at a time. The optimum setting will vary from application to application.

The location of the odbc.ini file must be determined once the correct modifications have been made and saved to the odbc.ini file. The driver will look, by default, to see if the ODBCINI environment variable exists. The driver expects that ODBCINI environment variable be exported into the environment to provide the full path and filename. For example:

ODBCINI=/usr/dlc/wrk/odbc.ini

Identifying the odbc.ini file in this manner provides a way to have one INI file in a shared location. This enables all ODBC clients to share a single INI file. The default location for the driver to look if the ODBCINI environment variable is not set is in the $HOME directory for a .odbc.ini file.

Note: The .ini file must be prefixed with a period.