select a.table_name,

       t.comments,

       a.COLUMN_ID,

       nvl(b.comments,b.column_name),

       b.column_name,

       a.DATA_TYPE,

       case

         when a.DATA_TYPE = 'VARCHAR2' then

          a.DATA_TYPE || '(' || a.DATA_LENGTH || ')'

         when a.DATA_TYPE = 'DATE' then

          ''

         when a.DATA_TYPE = 'NUMBER' and a.DATA_SCALE is not null then

          a.DATA_TYPE || '(' || a.DATA_PRECISION || ',' || a.DATA_SCALE || ')'

         when a.DATA_TYPE = 'NUMBER' and a.DATA_SCALE is null then

          a.DATA_TYPE || '(' || a.DATA_LENGTH || ')'

         else

          ''

       end case,

       case

         when (select nvl(count(1), 0)

                 from user_cons_columns c, user_constraints d

                where d.constraint_name = c.constraint_name

                  and d.constraint_type = 'P'

                  and c.table_name = a.table_name

                  and c.column_name = a.column_name) = 1 then

          nvl((select d.constraint_name

                 from user_cons_columns c, user_constraints d

                where d.constraint_name = c.constraint_name

                  and d.constraint_type = 'P'

                  and c.table_name = a.table_name

                  and c.column_name = a.column_name),'')

         else

          ''

       end case

  from user_tab_cols a, user_col_comments b,user_tab_comments t

where a.TABLE_NAME = b.table_name

   and a.COLUMN_NAME = b.column_name

   and a.table_name=t.table_name

   order by a.table_name,a.COLUMN_ID;