How to model my structured data?

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wim
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How to model my structured data?

Post by wim »

Hi,

I have a large "configuration" object that is a hierarchical structure of primitive variables. Say, a few thousand primitives organized in a hierarchy of 10 levels deep.

I can model this configuration any way I want, e.g.
1) as a structured variable (1 node)
2) or, as a hierarchy of individual nodes

I am wondering, does one of these options allow me to
- read all this data at once
- and, read just a part of this data


I guess what I need is something like IndexRange for arrays, so that I can specify if I want to read the whole array at once, or just part of it. Does something similar exist for structured variables please?

Thank you for your insights!

Wim

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Re: How to model my structured data?

Post by Support Team »

Hi Wim,

You can expose the information as a Variable with a structure data type that contains all information. This allows you to read everything in one Read operation from one node.

In addition you can expose all structure elements as child variables below the variable with the whole structure. This allows access to single elements of the structure.
There is currently no IndexRange functionality for structure element access in OPC UA.
Best regards
Unified Automation Support Team

wim
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Re: How to model my structured data?

Post by wim »

Hello,
Thanks for the info! I think indeed this is the best way, as it leaves all options open for the client.
Kind regards,
Wim

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