表建立完成後使用下列命令新增列的註釋：

comment on column 表名.欄位名 is "註釋";表的註釋：yang@rac1desc user_col_comments

Name Null? Type

-------------------------- -------- ------------

TABLE_NAME NOT NULL VARCHAR2(30)

COLUMN_NAME NOT NULL VARCHAR2(30)

COMMENTS VARCHAR2(4000)

yang@rac1comment on table tchar is " 這是一個測試表";

Comment created.

yang@rac1select table_name ,comments from user_tab_comments;

TABLE_NAME COMMENTS

------------------------------ -----------------------

TCHAR 這是一個測試表

表中欄位的註釋：

yang@rac1desc user_col_comments

Name Null? Type

------------------------ -------- ----------------------------

TABLE_NAME NOT NULL VARCHAR2(30)

COLUMN_NAME NOT NULL VARCHAR2(30)

COMMENTS VARCHAR2(4000)

yang@rac1comment on column tchar.val is " 測試 來自客戶 ";

Comment created.

yang@rac1col comments for a45

yang@rac1select comments from user_col_comments where table_name="TCHAR" and column_name="VAL";COMMENTS

測試 來自客戶