What creates new Tag IDs and consequences

Ignition
1

As I'm developing and refining tags and methodologies, I wonder what kind of adjustments create new tag id's to an existing tag. While I am concerned about background issues (multiple instances, orphaned remnants, other leftovers I'm not aware of), I'm very concerned about breaking tag history. For example, if I modify the OPC Server or Item Path, will history be disrupted? We deal with lots of UDTs, and I'll make adjustments for scan rates, deadbands, etc. and those do not have an apparent effect.

Is history just linked to the tag id?

Is my concern limited to modifying the tag path/tag name?

What work on tags would cause a lot of background clutter or memory/performance issues?

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2

i think that basically any edit to settings besides tag name should preserve ID, based on what's happening under the hood afaict?

but ymmv, someone from the ignition team should probably comment here

3

In my experience, changing the tag path (or name by extension) or toggling history on will generate a new tag id. Scan classes, datatypes, and query mode can be updated in the record while maintaining the same id.

Only changing that ID will "break" history. But it isn't really broken, its just stored under a different tag id.

Tag history does not care about OPC Server or item path.

Even if you were to need to cause a new ID to be assigned to a tag path, it isn't too much work to go back in and syncronize the data records to the new id. The data isn't lost until it is pruned from the DB.

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