A union offers the possibility to mix several data sets. The source data does not have to have identical attributes (column names). If identical attributes are present, the same column is written to.

An example:

Data Set 1:

dog name breed color
Waldo dachshund brown
Wasti hybrid colorful
Bello poodle black

Data Set 2:

cat name breed favorite food
Fluffy persian cat fish
Hugo maine-coon-cat schnitzel
Mason sibirian cat shoes

These two tables have a common attribute(breed). The union creates the following table with 6 records (rows) and 5 attributes (column names):

dog name breed color cat name favorite food
Waldo dachshund brown undefined undefined
Wasti hybrid colorful undefined undefined
Bello poodle black undefined undefined
undefined persian cat undefined Fluffy fish
undefined maine-coon-cat undefined Hugo schnitzel
undefined sibirian cat undefined Mason shoes

Create a Union

A new union is created, as with all operations, by dragging the icon from the side menu bar onto the graphical flow editor.


At the beginning a union has 2 inputs. If these two are connected, a further input automatically appears which can be connected.


This automatic expansion continues up to a maximum of 10 inputs. Inputs can be removed by deleting the connection.

Configuration, start and evaluation


  1. Apart from a (meaningful) name nothing can and must be configured.
  2. The execution is started with UNITE.
  3. History and metrics are available after the execution.
  4. The result can be examined in the table view below.

Afterwards the data is available at the output for further flow operations.