String manipulation: Create "Route" column

Step 1: Click on the node to open the configuration window.

Step 2: In the "Expression 1" section, enter the following expression: $["Origin"] + "-" + $["Dest"]

This will concatenate the origin airport with the destination airport with a hyphen in between. Choose the "Append" option and name the new column ''Route''.

Step 3: Select "Apply and Execute" to append the new column to the output table.

Implement logic: Create "Status" column

Step 1: Click on the node to open the configuration window.

Step 2: In the "Expression 1" section, enter the following expression: if($["DepDelay"]>15,"Delayed","Not Delayed")

This will create a rule, where all flights with departure delay>15 will be assigned the status "Delayed"while the restof the flights wiill be labeled as "Not Delayed". Choose the "Append" option and name the new column "Status".

Step 3: Select "Apply and Execute" to append the new column to the output table.

Transform Data: Expression

This workflow demonstrates the usage of the Expression node for data transformation: String manipulation and logic implementation.

The objective of the workflow is to summarize the airline dataset, analyze the delayed flights, and provide route details.

Workflow complete!

Keep the momentum going by exploring Just KNIME It! on the Hub to challenge yourself and see how these nodes can be integrated into more complex workflows and use cases.