if column exists

Dear all,

I have to check a table if a column exists.

If yes (column is already existing): column values should be set to null

if no(column is not existing): column should be added.

in pseudo code:

if exists (column"test") then

all column(“test”)=null

else

add column(test)

In forum I found an node if column exists from column, but I can’t find it.

Is there a smart way to realize?

Thanks for help!

BR,

Heinz