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Join operator


The Join operator merges multiple inputs in one composite output.
It's useful when designing a parallel portion of the workflow where you need to process the same information with different models. You first use the Fork operator to pass the input to two or three models, then merge the models' results with Join.

A Join must have two or three input connections to upstream blocks to be considered valid.
It can be the last block of the workflow.


The output of a Join block is the composition of the outputs of its upstream blocks and has this structure:

        first block ID:{
            first block output body
        second block ID:{
            second block output body
        third block ID:{
            third block output body

Block properties

Block properties can be set by editing the block.
A Join operator block has these properties:

  • The unique block ID and the service version, displayed in the title bar (read only, displayed also in the block tooltip in the canvas).
  • Block name