Transaction group not evaluating properlly on "evaluate when tags change"

[richardNZ15]

Hi guys,

I have a pretty basic recipe style standard transaction group set up.
The intention is to link a database table to some OPC tags such that the OPC tags will be updated when ANY tags change, whether that be an OPC tag trigger, or any values in the database table.

I have set it up as a DB to OPC connection, with trigger set to evaluate when ANY tags change.

I have tested it and its not working as i’d expect.

It doesn’t evaluate when i change the SQL database which i’d want it to do, unless i disable “only evaluate when values have changed”.

Please see the attached screenshot of the configuration.

[pturmel]

You have a chicken vs. egg problem. You want to update when any data in the DB changes, but the transaction won’t execute the query until it is triggered. You’ll have to simply use a non-triggered transaction that executes every cycle.