code: private boolean isSelectAllColumns() {
      String columnProjection = this.getInputColumnProjection();
      if (columnProjection == null || columnProjection.trim().equals("*") || columnProjection.contains(".*")) {
        return true;
      }
      return false;
    }
docs: If input query is null or '*' in the select list, consider all columns.
  
  @return true, to select all colums. else, false.