ORACLE下刪除當前用戶下所有對象的SQL

ORACLE下刪除當前用戶下所有對象的SQL，這個是轉別人的，但是，做了修改和註釋
 

--刪除某個用戶下的對象
set heading off;
set feedback off;
spool c:\dropobj.sql;
  prompt --Drop constraint
 select 'alter table '||table_name||' drop constraint '||constraint_name||' ;' from user_constraints where constraint_type='R';
 prompt --Drop tables
 select 'drop table '||table_name ||';' from user_tables;

 prompt --Drop view
 select 'drop view ' ||view_name||';' from user_views;

 prompt --Drop sequence
 select 'drop sequence ' ||sequence_name||';' from user_sequences;

 prompt --Drop function
 select 'drop function ' ||object_name||';'  from user_objects  where object_type='FUNCTION';

 prompt --Drop procedure
 select 'drop procedure '||object_name||';' from user_objects  where object_type='PROCEDURE';

 prompt --Drop package
 prompt --Drop package body
 select 'drop package '|| object_name||';' from user_objects  where object_type='PACKAGE';

 prompt --Drop database link
 select 'drop database link '|| object_name||';' from user_objects  where object_type='DATABASE LINK';

spool off;
set heading on;
set feedback on;

@@c:\dropobj.sql;
host del c:\dropobj.sql;

--刪除某個用戶下的對象
set heading off;
set feedback off;
spool c:\dropobj.sql;
  prompt --Drop constraint
 select 'alter table '||table_name||' drop constraint '||constraint_name||' ;' from user_constraints where constraint_type='R';
 prompt --Drop tables
 select 'drop table '||table_name ||';' from user_tables; 
 
 prompt --Drop view
 select 'drop view ' ||view_name||';' from user_views;
 
 prompt --Drop sequence
 select 'drop sequence ' ||sequence_name||';' from user_sequences; 
 
 prompt --Drop function
 select 'drop function ' ||object_name||';'  from user_objects  where object_type='FUNCTION';

 prompt --Drop procedure
 select 'drop procedure '||object_name||';' from user_objects  where object_type='PROCEDURE';
 
 prompt --Drop package
 prompt --Drop package body
 select 'drop package '|| object_name||';' from user_objects  where object_type='PACKAGE';

 prompt --Drop database link
 select 'drop database link '|| object_name||';' from user_objects  where object_type='DATABASE LINK';
 
spool off;
set heading on;
set feedback on;

@@c:\dropobj.sql;
host del c:\dropobj.sql;

註釋：
1.上面這個語句，在pl/sql裏面是放在命令裏面執行的。
2.set heading off; 意思就是關閉表頭。如果不關閉，寫入dropobj.sql文件中就會帶有結果集的表頭如：
'DROPTABLE'||TABLE_NAME||';'
------------------------------------------
drop table TEACHER;
實際上我們需要的是“drop table TEACHER;”，“'DROPTABLE'||TABLE_NAME||';'
”就是表頭。
3.set feedback off; 意思就是關閉回顯。如果不關閉，寫入dropobj.sql文件中就會帶有返回結果集的大小等信息，如："137 rows selected"
4.spool c:\dropobj.sql; 把結果集寫入這個文件。spool off; 結束寫入。
5.@@c:\dropobj.sql; 執行這個sql
6.host del c:\dropobj.sql; 刪除主機上這文件。
7.CONSTRAINT_TYPE 就是鍵的類型：
 

C (check constraint on a table)
P (primary key)
U (unique key)
R (referential integrity)
V (with check option, on a view)
O (with read only, on a view)

C (check constraint on a table) 
P (primary key) 
U (unique key)
R (referential integrity)
V (with check option, on a view)
O (with read only, on a view)

8.當執行'drop package ………… '這句時，package body會被同時刪除。