Question: How to filter events on subscription with where_clause about opcua-asyncio HOT 2 OPEN

First some server maynot support the complete eventfilter specification. So this could be an issue. Also we just send the Filter as you specify it to the server, so you need to read the OPC UA specification and follow it.
From the spec see https://reference.opcfoundation.org/Core/Part4/v104/docs/7.4.1 :

The filter is evaluated by evaluating the first entry in the element array starting with the first operand in the operand array. The operands of an element may contain References to sub-elements resulting in the evaluation continuing to the referenced elements in the element array.

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Hi Schroeder,

thanks for your reply.

After reading the referenced link, my life is actually not easier.
I still can`t figure out, how to use multiple filter element connected by logical operands.
Therefore, I reworked my code to use only one filter element.

An example for filtering events by attributes, would be appreciated in the future.

Regards,
Harald

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