This page is no longer maintained (Nov 12, 2025). For the most current information, go to Union.

Snap type:

Flow

Description:

This Snap is used to merge document streams into a single output stream.

To join two or more data streams, see the /wiki/spaces/AP/pages/1439005 Snap.

Prerequisites:

[None]

Support and limitations:

Works in Ultra Tasks.

Account:

Accounts are not used with this Snap.

Views:

Input	This Snap has at least one document input view.
Output	This Snap has exactly one document output view.
Error	This Snap has at most one document error view and produces zero or more documents in the view.

Settings

Label

Required. The name for the Snap. You can modify this to be more specific, especially if you have more than one of the same Snap in your pipeline.

Snap Execution

Select one of the three modes in which the Snap executes. Available options are:

Validate & Execute: Performs limited execution of the Snap, and generates a data preview during Pipeline validation. Subsequently, performs full execution of the Snap (unlimited records) during Pipeline runtime.
Execute only: Performs full execution of the Snap during Pipeline execution without generating preview data.
Disabled: Disables the Snap and all Snaps that are downstream from it.

Default Value: Execute only

Example: Validate & Execute

Example

Combine data without any matching key or condition using Union Snap

This example pipeline demonstrates how to append records from multiple sources without needing a matching key between two files using the Union Snap. It combines order information, that is items and costs with the customer details. The pipeline comprises two segments, each independently generating JSON data, which are then merged with a Union snap.

Configure the JSON Generator Snap with input data as shown below.
Next, connect the Union Snap to the upstream Snaps. The Union Snap combines the output from both JSON Generator snaps, merging the order and customer data into a single stream.
Upon validation, the Snap displays the following joined output as a result of providing a consistent input schema. Note that though the customer_id is common for both the input Snaps here, the Union Snap simply appends the data from both of them.

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