Inserting Data into SQL database using OPCUA subscription mode

Hi Guys!

With OPCUA read node and MySQL node, i can inject the PLC value into SQL database. And table looks as below.


What i like to know that with OPCUA subscribe node, is it possible to feed data into SQL database as well. Because with subscription, we get only those values in node-red flow which changes. As a result i cannot able to form the array to insert values into SQL database. I cannot able to figure out how to push the data in the SQL table in the same manner as we did with read mode.

Everywhere in tutorial/ YT videos, peoples have used 'OPCUA read mode' instead of 'OPCUA subscribe mode' to log PLC data from node-red to SQL databases. Why is that? I mean why people do not use subscribe mode to log data into databases. Isn't it is categorically stated that subscribe mode reduces the load on the PLC?

Thanks in Advance!