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This gem runs in .

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Overview

The Union gem lets you combine records from different tables for cases such as merging customer databases or aggregating logs from multiple servers.
The gem has a corresponding interactive gem example. See Interactive gem examples to learn how to run sample pipelines for this and other gems.

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Input and Output

To add additional input ports, click + next to Ports. All input tables must have identical schemas (matching column names and data types). If table columns have different orders or a different number of columns, use the UnionByName gem.

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Parameters

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Example

Let’s say you’re working with two tables: Table A and Table B.
  • Both tables contain order-related data.
  • Table A contains order information from customer 1, 2, and 3.
  • Table B contains order information from customer 1, 2, 3, and 4.
  • These tables contain some identical records (duplicates).

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Table A

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Table B

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Result without duplicates

The following is the output table without duplicates.

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Result with duplicates

The following is the output table when you select Preserve duplicate rows in the gem configuration.
Order 103 and 104 are duplicate records.