Variable aggregator

[ccc81555]

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Why is my 'variable aggregator' not working properly? I hope it's the output of the two knowledge bases that were aggregated earlier. There is a background here, which is that this is the same knowledge base, but there are multiple sub documents inside. I used a large model to output different questions, divided them into two queries, and then aggregated them into the variable aggregator for the next large model to use. However, I found that the variable aggregator is not working. The first two knowledge bases can output corresponding information, but when the variable aggregator outputs, it only outputs the content of the first knowledge base

@dosu

[dosubot[bot]]

The variable aggregator in Dify is currently designed to select and output only the first non-null result from its inputs (or the first per group if advanced grouping is enabled), rather than merging or concatenating results from multiple knowledge base queries. This is intentional and documented in both the code and workflow test fixtures—so when you aggregate, you only get the first result, not a combined output from all sources [source].

If you need to merge outputs from multiple knowledge base queries, you’ll need to use a custom node, post-processing step, or combine the results before passing them to the aggregator. If merging is a common need, consider requesting a feature for true concatenation/merging support in the aggregator.

To reply, just mention @dosu.

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