code: private void validate(List<ByteBuffer> variables) throws InvalidRequestException
      {
          // Ensure that exactly one key has been specified.
          if (keyValidator.size() < 1)
              throw new InvalidRequestException("You must specify a PRIMARY KEY");
          else if (keyValidator.size() > 1)
              throw new InvalidRequestException("You may only specify one PRIMARY KEY");
  
          AbstractType<?> comparator;
  
          try
          {
              cfProps.validate();
              comparator = cfProps.getComparator();
          }
          catch (ConfigurationException e)
          {
              throw new InvalidRequestException(e.toString());
          }
          catch (SyntaxException e)
          {
              throw new InvalidRequestException(e.toString());
          }
  
          for (Map.Entry<Term, String> column : columns.entrySet())
          {
              ByteBuffer name = column.getKey().getByteBuffer(comparator, variables);
  
              if (keyAlias != null && keyAlias.equals(name))
                  throw new InvalidRequestException("Invalid column name: "
                                                    + column.getKey().getText()
                                                    + ", because it equals to the key_alias.");
  
          }
      }
docs: Perform validation of parsed params