Yes, I think that is exactly the reason why the performance is slow sometimes: When a button sends a command back to the table the whole data is coming back and is being processed by the flow. I'll have to look at that more critically, maybe I can simply filter that out..
Yes, I have utilized many of your great examples in other threads here where you demonstrate the updateOrAddData command and that just works wonderfully.
Slowly, but surely, the whole concept of callbacks and commands sinks in and I'm really looking forward to implement more cool features like - as you mentioned the bulk editing which is another task on my huge todo list.. 
So far I see no performance issues with loading the data. A default filter (that applies a where clause directly into the SQL select) caps the result set to only items from the last week, so that's helping a lot. In the rare case, where I wanna see data of an unlimited timespan the table still loads fine. I'll have to wait for the day when it reaches 500k entries 
One nice feature I often use are global or flow context variables which hold computational results that would otherwise be way too expensive to be re-calculated every time a flow (with a table or chart) is being loaded. But for the table with all the stock data there was so far no problem yet.
Looking forward to learn more knowledge & good practices, so it becomes a natural thing to develop amazing flows!
Seriously, without Node Red I wouldn't have come that far* 
(*So far my flows contain several dozen REST endpoints (using GET & POST), 2 different databases are employed (MySQL and Mongo, as you might remember 
), a whole load of flows with tons of tables, forms and charts. The development speed finds no comparison to common Java programming! Over 20 pages with a lot of complexity, good looking UI (special thanks to @TotallyInformation for his amazing UIBuilder!) and a very easy way to achieve good UX... all done within less than 5 months!
And yet, during just 1 week my Trello board is gaining more tasks than I can work them off .. hahaha
