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.