Tag History Provider special specifier value [~]

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I haven't been able to find this in the user manual (~ is impossible to search for, along with . as in [.] for tags!). But my understanding is that, for a reference to a tagpath in a tag binding, [~] tells the binding to use the project's default tag provider?
For a tag history binding I would assume the same, but where does the tag history provider and the other parts come from?
E.g. you would normally have to provide:

  • Database name
  • Gateway name
  • Tag Provider name

For context, I'm looking at a project that has a backend and frontend gateway. The backend hosts the tag and tag history providers. The frontend hosts Perspective and Vision, and has remote tag and tag history providers linking back to the backend's. One caveat is that the frontend's remote tag providers have different names to those in the backend. For brevity, an issue was resolved in renaming them, however it was certainly not the intention to have them different.

I'm trying to work out why easy charts in frontend Vision aren't showing any data. They're using tagpaths like [~]tag/path. When I use a full tagpath e.g. [DatabaseName/GatewayName:TagProvider]tag/path where the names are taken from the Backend, it works. Really, I need to know what [~] is resolving to, as I suspect the name mismatch is causing issues...

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I didn't mention it (I forgot about it), but to reduce GAN traffic, the remote tag providers are configured to use Database as the History Access Mode instead of GAN. I found that this was where my issue was, as the History Provider setting was using the frontend tag provider's name, not the backend tag provider's name :confused:

Although I'd still like to know where and how to find [~] and [.] mentioned in the User Manual, as they don't show up at all when searched for

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I believe this is what you were looking for:Tag Paths.. I searched for Tag Paths in the docs and it was the first item.

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