表、索引元信息的更新

/* update the time of the last modification (in handler::update_time) */
#define HA_STATUS_TIME           4
/*
  update the 'constant' part of the info:
  handler::max_data_file_length, max_index_file_length, create_time
  sortkey, ref_length, block_size, data_file_name, index_file_name.
  handler::table->s->keys_in_use, keys_for_keyread, rec_per_key
*/
#define HA_STATUS_CONST          8
/*
  update the 'variable' part of the info:
  handler::records, deleted, data_file_length, index_file_length,
  check_time, mean_rec_length
*/
#define HA_STATUS_VARIABLE      16
/*
  get the information about the key that caused last duplicate value error
  update handler::errkey and handler::dupp_ref
  see handler::get_dup_key()
*/
#define HA_STATUS_ERRKEY        32
/*
  update handler::auto_increment_value
*/
#define HA_STATUS_AUTO          64