The DataServer allows access to selected options defined in the ODBC interface by providing corresponding options that you can use with the -Dsrv startup parameter. Each OpenEdge-supplied ODBC option has a name of the form option-name and corresponds with a startup option in the ODBC interface having the name SQL_option-name. The following table lists the OpenEdge-supplied ODBC startup options and the corresponding startup options defined in the ODBC interface.

Table 1. ODBC options
OpenEdge-supplied option ODBC-defined option1
ACCESS_MODE SQL_ACCESS_MODE
ASYNC_ENABLE SQL_ASYNC_ENABLE
AUTOCOMMIT SQL_AUTOCOMMIT
LOGIN_TIMEOUT SQL_LOGIN_TIMEOUT
MAX_LENGTH SQL_MAX_LENGTH
MAX_ROWS SQL_MAX_ROWS
MSS_PRESERVE_CURS SQL_MSS_PRESERVE_CURS2
NOSCAN SQL_NOSCAN
OPT_TRACE SQL_OPT_TRACE
PACKET_SIZE SQL_PACKET_SIZE
QUERY_TIMEOUT SQL_QUERY_TIMEOUT
RESP_POLLCT SQL_RESP_POLLCT
RESP_TIMEOUT SQL_RESP_TIMEOUT
TXN_ISOLATION SQL_TXN_ISOLATION

When you specify an OpenEdge-supplied ODBC option with the -Dsrv startup parameter, the DataServer sends the option to the ODBC driver for processing by the ODBC interface.

The following example of the -Dsrv startup parameter tells the ODBC driver to return no more than 1,000 rows to the OpenEdge application:

-Dsrv MAX_ROWS,1000
Note: The DataServer generally sets the correct value automatically. Therefore, you should reserve use of the ODBC options for troubleshooting and fine-tuning purposes only.
1 Refer to an ODBC application developer's guide for information on the ODBC-defined options.
2 Cursor preservation allows server side cursors to be preserved beyond the transaction boundary. See Preserve cursors: the -Dsrv MSS_PRESERVE_CURS,1 option for information and warnings.