code: @Override
      public BooleanExpression ne(Expression<? super T> right) {
          if (right instanceof RelationalPath) {
              return primaryKeyOperation(Ops.NE, primaryKey, ((RelationalPath) right).getPrimaryKey());
          } else {
              return super.ne(right);
          }
      }
docs: Compares the two relational paths using primary key columns
  
  @param right rhs of the comparison
  @return this != right