MYSQL_FIELD *
mysql_fetch_fields(MYSQL_RES *result)
          Returns an array of all MYSQL_FIELD
          structures for a result set. Each structure provides the field
          definition for one column of the result set.
        
          For metadata-optional connections, this function returns
          NULL when the
          resultset_metadata system
          variable is set to NONE. To check whether a
          result set has metadata, use the
          mysql_result_metadata()
          function. For details about managing result set metadata
          transfer, see Section 3.6.7, “Optional Result Set Metadata”.
        
          An array of MYSQL_FIELD structures for all
          columns of a result set. NULL if the result
          set has no metadata.