AlterQuery  t (children 2)
 ExpressionList (children 1)
  AlterCommand ADD_PROJECTION (children 1)
   Projection (children 1)
    ProjectionSelectQuery (children 1)
     ExpressionList (children 1)
      Function uniqHLL12 (children 1)
       ExpressionList (children 1)
        Identifier x
 Identifier t
