How to pass data between iterations in a loop?

[Ars_N]

I want to achieve what seems like a very basic thing:
An AI should loop over a database, gradually building up its “understanding” during the loop.

So I don’t need a loop over predefined items — I need a standard cycle with accumulation.

The idea:

AI looks at the user prompt, prepares a query,

Executes the query, gets a response,

Prepares a new query based on the response,

And gradually builds a research report over multiple iterations.

I tried using this approach:

Incrementing Your Own Loop Variable

Controlling your own loop in n8n can get a little tricky because you have to use values from nodes that are in scope before the loop (initialized) AND within the loop (updated/incremented). This makes use of the node.isExecuted built in variable, and a JS ternary operator, to decide whether to use the initial value or the value from the last iteration of the loop. Examine the expression in the Increment Loop Var node for details. Key elements to making this work. All…

But it didn’t work — I get an error saying the node doesn’t exist.

How should I properly implement this behavior in n8n?
Or this is not task for n8n?

[interss]

Hi @Ars_N

Open a separate workflow and test this suggestion below.

Remember to check the credentials and adjust as needed.

If you find any part in Portuguese, translate it to your language, because I don’t speak English. So I need to take your message, translate it to Portuguese, understand the problem, see if I can help in any way, answer the question, translate it to English and then post it to the community. I wish you all the best!

If this suggestion solved your problem, please mark my post as a solution (blue box with check mark) so that this ongoing discussion does not distract others who want to find the answer to the original question and click the heart. Thank you

[Ars_N]

Thanks. I did it

Summary

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              "leftValue": "={{ $json.i }}",
              "rightValue": 9,
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                "operation": "gt"
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      "name": "Code1"
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    {
      "parameters": {
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  "pinData": {},
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    "Code1": {
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  "active": false,
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  "id": "MKFdNvFow8w2ky3j",
  "tags": []
}```

Interesting why is so not obviously for implementation? Just loop… n8n, what you are?