Renaming array elements after join

General
1

I have joined two payloads to an array.

How would one replace the array element numbers to a custom string?
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I tried using the change node and move payloads, without success.

2

An array has numeric indices.
Can't you set the join node to create a key/value object?
The resulting object would use msg.topic as the element names

3

You are right. I did try, but did not use msg.topic in the change node. It works now. Thanks!
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