查詢表字段明細

select  column_name,data_type,data_length,DATA_PRECISION ,DATA_SCALE 
from all_tab_columns where table_name='tablename'

字段注釋

select   *   from   user_col_comments;

表注釋

select   *   from   user_tab_comments;

表明細+表注釋+字段明細+字段注釋

select  ATC.OWNER,atC.TABLE_NAME,utc.comments,ATC.COLUMN_NAME,ATC.DATA_TYPE,ATC.DATA_LENGTH,ATC.NULLABLE, ucc.comments from

(select ATC.OWNER,atC.TABLE_NAME,ATC.COLUMN_NAME,ATC.DATA_TYPE,ATC.DATA_LENGTH,ATC.NULLABLE
from all_tab_columns ATC where ATC.owner in (用戶名1，用戶名2........) ) atc

left outer join user_col_comments ucc on atc.table_name=ucc.table_name and atc.column_name=ucc.column_name

left outer join user_tab_comments utc on atc.table_name=utc.table_name

order by atc.table_name,atc.column_name