title: Use of updategram to describe a 'not' condition in before filter
body: <p>In use of update gram to update a table in DB2, the previous developer used update gram but the filter was not done right, requirement is if do the update if certain column 'is not' of some value.</p>
  
  <p>Not really used much of updategram, I know how to do the filter if the column 'is' of some value, but how to achiever this 'is not' condition?</p>