Transaction groups optimization?

Ignition
1

Not familiar enough with Ignition yet to see if or how something like this can be done.
Example:
I have two Expression Tags tagA, tagB that are not based on machines.
Currently we have a transaction group monitoring the change in each of the tags.
However they call the same procedure, which has 3 parameters,

  1. The value of tagA or TagB
  2. A dependent OPC Expression Tag (ie if it is the transaction group for tagA, we will use tagAA, tagB will use tagBB)
  3. a dependent Fixed triggered expression item ( tagA will always use X, tagB will always use Y)

So basically I want to accomplish the following in one single “trigger” :
if tagA changed, i want to call procedure123 with tagA.value, tagAA.value, “X”,
but if it is tagB that changed, then call procudere123 with tagB.value, tagBB.value, “Y”

Things could be simplified since in our in our current environment tagAA, and tagBB have the same value, but there is nothing that could prevent that being different in the future.

There is also the chance that additional SQL Tags to be monitored could be added, ie TagC, TagD, though that would be highly unlikely.

As to the why of reducing this - well it seems it would be more efficient to have fewer transaction groups and fewer items to maintain.

Looking forward to any ideas and suggestions
Mark

2

You can create expression items in the group that can detect if a tag value has changed. The expression would be:hasChanged({[.]tagA})Using that you can have three expression items mapped to the 3 parameters of the stored procedure. Each expression would look like this:if(hasChanged({[.]tagA}), {[.]tagA}, {[.]tagB})Of course the value retured would be different for each. This is a starting point.

3

Thanks Travis,
I missed that haschanged function when I was looking for such a function.
At least now I have something with which to experiment.