I’m sorry your having trouble w/OptoDataLink. I’ve forwarded your info to our support team so they can help you troubleshoot. (They’ll want to know the version of ODL you’re using, etc.)
In the meantime, might you be connecting your SQL database to a SNAP-PAC-R or -S series controller, running 9.5 firmware? I ask because the RESTful API in the 9.5 firmware opens up an exciting variety of new options for connecting your controller tags to database, without the middleware!
Check out these examples: http://developer.opto22.com/2016/10/18/sql-server-2016-code-sample/