I’m a newbie in node red!
I would like to show dynamically multiple data points in a single chart.
I found this great video sample:
Flow sample at:
All function well but, sometimes, the showing of multiple data points in chart doesn’t function as expected.
The problem is that, sometimes, some data points are missing or exceeding as expected.
Using debug node I note that function node “SQL”, that produce the multiple “SELECT” for database “DB” node, works always well (if operator select 3 search key function produce 3 “SELECT” in an array and so on).
After “DB” node there is a “Edit Join” node that should combine each msg.payload produced by “DB” node to create an array that will be elaborated by a “Prep” function node that feed data in “Chart” node.
Putting a debug node after the “Edit Join” node it seems that sometimes (not always) are missing or exceeding some elements in array (for example from “DB” node exit 4 msg.payload but after “Edit Join” node only 2 or 3 are produced and so “Chart” node doesn’t show the correct data.
My opinion is that, for strange reasons, “Edit Join” node starts elaboration before that “DB” node has finished to produce all the data.
In fact, if for example the operator selects 5 search keys, observing the debugging I note that sometimes first 3 Payload come out from the "DB" then the array Payload exits from the "Join" and then the last 2 Payloads come out from the “DB” and so are no longer considered by the "Join".
I also try to configure Join node using "Send the message after a timeout following the first message" but without results (indeed it seems that it is worse...)
Why in your opinion?