COMMENT ON   { TABLE [ schema. ]     { table | view }   | COLUMN [ schema. ]     { table. | view. | materialized_view. } column   | OPERATOR [ schema. ] operator   | INDEXTYPE [ schema. ] indextype   | MATERIALIZED VIEW materialized_view   } IS 'text' ;

comment on table table_name is 'comments_on_tab_information';

comment on column table.column_name is 'comments_on_col_information';

SQL> select * from user_tab_comments where TABLE_NAME='EMPLOYEES';

TABLE_NAME                     TABLE_TYPE  COMMENTS ------------------------------ ----------- ---------- EMPLOYEES                      TABLE       员工表 SQL> select * from user_tab_comments where comments is not null; TABLE_NAME                     TABLE_TYPE  COMMENTS ------------------------------ ----------- -------------------------- EMPLOYEES                      TABLE       员工表

SQL> select * from user_col_comments where TABLE_NAME='EMPLOYEES';

TABLE_NAME                     COLUMN_NAME                    COMMENTS ------------------------------ ------------------------------ ------------ EMPLOYEES                      EMPLOYEE_ID                    EMPLOYEES                      MANAGER_ID                     EMPLOYEES                      FIRST_NAME                     EMPLOYEES                      LAST_NAME                      EMPLOYEES                      TITLE                          EMPLOYEES                      SALARY                         员工薪水 SQL> select * from user_col_comments where comments is not null; TABLE_NAME                     COLUMN_NAME                    COMMENTS ------------------------------ ------------------------------ ------------- EMPLOYEES                      SALARY                         员工薪水

ALL_COL_COMMENTS USER_COL_COMMENTS ALL_TAB_COMMENTS USER_TAB_COMMENTS

SQL> comment on table employees is ''; Comment added SQL> select * from user_tab_comments where TABLE_NAME='EMPLOYEES'; TABLE_NAME                     TABLE_TYPE  COMMENTS ------------------------------ ----------- ------------- EMPLOYEES                      TABLE     

SQL> comment on column employees.salary is ''; Comment added SQL> select * from user_col_comments where TABLE_NAME='EMPLOYEES'; TABLE_NAME                     COLUMN_NAME                    COMMENTS ------------------------------ ------------------------------ ------------- EMPLOYEES                      EMPLOYEE_ID                    EMPLOYEES                      MANAGER_ID                     EMPLOYEES                      FIRST_NAME                     EMPLOYEES                      LAST_NAME                      EMPLOYEES                      TITLE                          EMPLOYEES                      SALARY