To remove a condition column, you can either right-click on the column name in the "Columns in use" section and select "Remove":
Or select the column and click on the trash can icon at the top right of the column properties editor:
Then Save the editor configuration, and proceed to test and deploy the new policy version.
Notes:
- Columns which show a lock icon cannot be removed, as they are either required for the correct functioning of the table, or contain custom logic which cannot be restored
You can hide such columns instead by unchecking the "Visible?" box. Make sure to remove any data in column cells from the policy first -- conditions will continue to be applied even if a column is hidden, which can be confusing. - You cannot change the field to which a column refers
To change a column field, delete the old column and create a new one as described in How do I add a condition column to a Decision Table?