Help center Get started Knowledge center Product documentation API documentation
Product
Lens Weave Maskbits
Overview
Data
Data Import Output Result
Data Preparation
Cleansing Imputation Duplicates Filter Fuzzy Filter Outlier Treatment Binning Trimming Validation Sorting
Transformation
Data Transformation Bulk Data Transformation Merge Union Fuzzy Merge Encoding Normalization Scaling Standardization Aggregate Unpivot Functional Transformation SQL Executor
Statistical Plots
Box Plot Correlation Histogram Pair Wise Line Plot Scatter Plot Bar Plot Stem Plot Step Plot Fill Between Stack Plot Descriptive Statistics
Workflow Agent
Workflow Agent
Scheduler
Scheduler
Library
My Workflows Shared Workflows Audit
Datasource
Datasource
Datasource Management
Data Model
Connectors Management
Admin
Admin
User Management Roles Management Group Management Organization Management

Overview

The Union node is a transformation node in a Weave Workflow that combines two or more upstream data sets into a single output table. It sits in the middle of a Workflow’s processing path — between source nodes (Data Import) and terminal nodes (Result, Output) — and emits the unified data downstream. The node stacks the records from each connected input into one result set.

Union nodes are added from the node panel and require two or more connected inputs. The unified output adopts the configuration of the first schema imported, so the order in which inputs are connected determines the structure of the result.

Note: “Workflow” is the in-UI term for what some Weave documentation calls a pipeline. This reference uses “Workflow.”

When to use it

  • Combining records from two or more data sets that share a comparable structure into a single table.
  • Stacking data from separate Data Import nodes into one consolidated result set.
  • Producing a single unified table for downstream transformation, inspection, or output.

Inputs

InputDescription
Data Import nodesTwo or more upstream nodes connected to the Union node’s input.
Minimum inputsTwo connected data sets.

Structural reference

PropertyBehavior
Output schemaFollows the configuration of the first schema imported.
Result displayCombined data is shown as a table in the Result Tab after the node is run.
Configuration stateConfiguration must be saved or discarded; closing without either triggers a warning popup.

Key behaviors

Union is a transformation node. Unlike Data Import (source) and Result / Output (terminal), Union sits in the middle of the Workflow. It receives data from two or more upstream inputs, combines it, and passes the unified result downstream.

First-schema precedence. The unified table follows the configuration of the first schema imported. The order in which inputs are connected therefore determines the structure of the output.

Run-to-result. The combined result is not produced until the Workflow is run. After running, the result table is available through the Result Tab.

Save or discard enforcement. After configuring the node, the configuration must be explicitly saved to be retained or discarded to be undone. If neither is chosen, the platform displays a warning popup.