DESC

col tbl for a20 truncate
col data_len heading '桁' for a5
col comments for a20
bre on tbl skip page

set pages 500
select a.nullable,
       a.data_type,
       decode(a.data_type, 'NUMBER', data_precision || ',' || data_scale,
       'DATE', '', data_length) as data_len, a.column_name, b.comments, a.table_name as tbl
  from user_tab_columns a
  left join user_col_comments b
    on a.table_name = b.table_name
   and a.column_name = b.column_name
 where a.table_name in ('テーブル名称')
 order by a.table_name, a.column_id
;
set pages 53