Hi,
I have noticed this problem recently when I saw that hundreds of columns supposed to be removed were still in the sd file.
Weirdly, before this, I am sure that filtering the properties using a column filter node or by unselected them in a sdf writer was enough... I though it was due to a recent modification in Knime, but when I see this thread is 5 years ago, I am puzzled!
Anyway, the solution of Steve avoid using any other node, which is perfect.
Thanks,
Nicolas