In accordance with Zabbix documentation we have item key "db.odbc.select[unique_description,data_source_name]" to query a database via ODBC.
But in a case of LLD of databases on a host we haven't got a DSN on a Zabbix-server corresponding to discovered database. So, we need to add the DSN into odbc.ini and only after that we can use "db.odbc.select" to query discovered database. Therefore we lose a benefit of LLD.
It would be very useful if we can place a connection string like "DRIVER=
;UID=user;PWD=pass;" as a parameter "data_source_name" for an item prototype. It would allow us to avoid of using odbc.ini at all.
unixODBC (ver. 2.3.1 and above) lets use a connection string instead of DSN name for isql utility (-k option). It is desired to see similar feature in a future release of Zabbix.
As www.unixodbc.org state, function SQLDriverConnect must be used to allow such functionality.