title: QlikView field name as a dimension in expression
body: <p>My chart contains this dimension:
  <code>=if(vDim1='[Column1]','Column2',)</code>
  but if I do this I will actually have the value "Column2" written in every cell. </p>
  
  <p>How can I make QlikView interpret Column2 as a column name, as opposed to a value?
  I know it works if I use a variable vDim2 that is equal to: [Column2]:
  <code>=if(vDim1='[Column1]',$(vDim2),)</code>
  , but I am interested to know if there is a solution that doesn't use variables? Many thanks in advance!</p>