Incorrect Loop Wiring - Help...


So i have run into the following loop wiring error

This is in relation to the innermost loop in the below flow

The flow represents trying to solve the following:

  1. Connection reliability of Google Query Node - Solved with outermost recursive loop
  2. Avoid Sampling by requesting data at a daily granular level - Solved with middle loop.

I am now trying with the innermost loop to loop around the same date, where the number of rows returned is = 10000. This will solve for the pagination issue by causing additional request for the same day with incrementing start indexes.

but… it is not accepting the connection.

What am i missing? is there a solution?
@Iris - I tag you as having scoured the forum you appear to me most knowledgeable indeed about loops :grin:



So a few hours later, i have been able to solution all 3 issues i was workign on, the final one was solved using a recursive loop rather than a variable condition loop.

However if anyone knows why the above idea was giving the error i am very very curious to find out why.

preview of the solution below, (i had to change the order of the loops also, as it made more sense).

I’ll write up full methodology and share the component tomorrow.

Today was a lesson in knime looping, but loved it.


Hi @Gavin_Attard I had a similar error with a loop within a loop where the outer loop was a Table Row To Variable Loop Start node.
What I noticed is that for each loop-start you get a flow variable “Loop (…number…)”. For the outermost loop-start this will be “Loop(0)”. The second loop-start node should give you, next to this “Loop (0)” a new flow variable “Loop (1)”.
But it will do this only if it’s fed with this “Loop (0)” to begin with.
I had an own made component in between the two loop-start nodes which did not pass on this flow variable “Loop (0)”, so I made an extra variable connection to pass in on. This solved it for me.

Maybe those “Loop (…)” flow variables get lost somewhere in your initial workflow too?

Thanks @JanDuo - interesting observation, i hadn’t realised that they stack, i shall have a look today and see if this resolves it.