The HA Configuration object of a HistoricalDataNode

[sunny]

Hi Support team,

I am new to OPC UA Server, and trying to create a Historical Variable node by C++ sdk(Server).
In server tutorial lesson 7(Adding Support for Histrical Data Access), I found the samply source.
Now I wondered that
1. when implyment the History Access in a variable node, the HA Configuration object is 'must' or 'option'?
2. in part11
The Historical Access Data model extends the standard type model by defining the HistoricalDataConfigurationType.
This Object defines the general characteristics of a Node that defines the historical configuration of
any HistoricalDataNode that is defined to contain history.

would you please give me a information about the 'the historical configuration'.
It means the configuration for Internal Historizing or HistoryRead, or both of them ?

3. in sample source of lesson 7, Historizing Attribute is set to be True and the HA Configuration Object is set too in Step1～3.
But HA Configuration (and its compents) was not used in the Step 4～6.
What's the relationship between the Historizing Attribute and the HA Configuration Object ?


Regards
sunny

[Support Team]

Hello Sunny,

1) OPC UA Part 11 - 5.2.5 HistoricalDataNodes Address Space Model
"Each HistoricalDataNode with history shall have the Historizing Attribute (see Part 3) defined and may reference a HistoricalAccessConfiguration Object."

2) I guess "historical configuration" here just means an instance of this HistoricalDataConfigurationType.

3) The Historizing Attribute just indicates if the server is currently recording history for that Variable.
The HA configuration is optional and gives additional information about how the Data was collected, available aggregate functions and the aggregate configuration.
For detail please read on in specification part 11 and part 13.

[sunny]

Hi, support team

I got it.
Thank you for the hint.

Best regards