查看当前用户下所有表字段信息

SELECT s.table_name,
       s.column_name,
       decode(s.data_type,
              'DATE',
              s.data_type,
              s.data_type || '(' ||
              decode(s.data_type, 'NUMBER', s.data_precision, s.data_length) || ')') date_type,
       s.nullable,
       u.comments
  FROM user_tab_columns  s,
       user_col_comments u
 WHERE s.table_name = u.table_name
   AND s.column_name = u.column_name
 ORDER BY s.table_name