Gatway tag change script, getting id from db best practice

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1

I have a bunch of variable names in a database by id, then I read the database and create the tags in a folder. no udt, its just singular values, they only change once a week so not high frequency of change.

I have a tag change script watching the folder and when a variable changes, I insert the value into a table. The tags are created by name with no reference to the id in the table.

I wanted to insert the id and value to reference back to the variable table and I am trying to figuire out the best practice way to achieve this.

I was thinking of maybe creating a UDT with both the value and ID but that still involves me reading another tag when the tag change script executes.

I also though of maybe appending the id (_1, _2, etc..) at the end of the name and then I could read it from the tag name when the tag change script executes.

Any other suggestions or better ways than what I am thinking? thanks!

2

At the time you create the variables by reading from the ID, store the ID in a custom property of the tag. Then your tag change event can read the ID from the custom property.

3

I didn't know that was an option, thanks

4

How do I access the custom property from the gateway tag change script? I tried going through event, newValue, getproperty, etc... I'm sure this is right in front of me too.

I just ended up readBlocking the path, I was hoping to access it directly from the tag that called it if possible but this is fine too. Thanks

5

system.tag.readBlocking() using the event's tag path and appending .somePropName.

6

Thanks, that's what i ended up doing. I was hoping it would come along in the event without doing an extra readBlocking.