Table Writer -- Append if file exists

Hello,
The Table Writer node should have an option to append data if the file already exists, like the CSV writer node:

Thank you

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@tobias.koetter love the idea :slight_smile:

@Snowy we’re currently thinking about adding a feature along those lines - can you maybe describe your use-case for that feature a bit? Maybe we’re already on to something similar (e.g. we’re also discussing versioning of tables).

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Hi @christian.dietz
Yes, happily… I have a workflow where an R snippet is inside a loop. The “Loop End” node appends the results of the loop automatically. But in this instance, I need multiple tables from my R snippet, which requires multiple “R to Table” nodes. And since I can’t have two “Loop End” nodes, I need some way to collect the results of the loop – So I write to a CSV, simply for the purpose of reading it back into the same workflow for later processing/evaluation.

Here is what my workflow looks like visually:

I hope this makes sense, and maybe there is another way to solve this problem. I simply was going to use the “Table Writer” node in place of CSV because of the file write/read size/speed. It would be ideal if there was a way to collect the results of the loop without actually having to write to a file.

Hello @Snowy,

For next release dynamic loop end support is planned and is actually part of nightly build so feel free to give it a try :wink:

https://www.knime.com/nightly-build-downloads

Still append option within Table Writer node seems reasonable to me :slight_smile:

Br,
Ivan

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