Adding NULL value to row in KNIME

Question

Does anyone know if it is possible to add a null value to a row in KNIME?

I am trying to use the Rule Engine to remove some values, and substitute them with a NULL.

Regards

Answer 1

There is no syntax (as of KNIME 3.4.0) for declaring missing values from Rule Engine nodes. There are workarounds though:

1. When you specify which case should have non-missing values, the non-matching rows will be missing:

   If no rule matches, the outcome is a missing value.

2. You can have a column with all-missing values with the proper type and set that column as the outcome, like ... => $missingIntCol$

With the Rule Engine (Dictionary) node the outcome column cannot contain missing values.)