code: public EsIndexColumn column(String name) {
          return columns.get(noprefix(name, 
                  EsIndexColumn.LENGTH_PREFIX,
                  EsIndexColumn.LOWERCASE_PREFIX,
                  EsIndexColumn.UPPERCASE_PREFIX));
      }
docs: Gets column with given name.
  
  @param name the name of column in index or name of pseudo column like
  lower case, upper case or length.
  
  @return real column definition related to the specified name