Merge Variables

Merges flow variables into one stream. This node aggregates variables defined in different input connections into one variable connection. It does not modify variables but only merges them. This node can also be used as a common barrier point to control the execution order of nodes, i.e. nodes connected to the output port will not start executing until all upstream nodes have been executed. Note, if there are the same variables defined in different inputs, a special conflict handling is applied: The top most flow variable input port will take priority and override values on conflicting variable names. Otherwise, the priority order goes from the bottom to the top port. For example, port 3 will take priority over port 2. However, the first port will always take priority over all other ports.

Input ports

1. Type: Flow Variable
   Flow variables of first stream
   Variables of the first stream.
2. Type: Flow Variable
   Flow variables of second stream
   Variables of the second stream.

Output ports

1. Type: Flow Variable
   Merged variables
   Flow variable combining all input variables.

input (Dynamic Inport)

Additional variables to merge.

1. Type: Flow Variable

External resources

• KNIME E-Learning Course: Creation and usage of Flow Variables in a KNIME workflow