ORACLE 10g 中恢复已删除的表_flashback
-- 笔记中部分内容
SQL> create table tt2 as select * from employee;
Table created.
SQL> drop table tt2;
Table dropped.
SQL> select * from tt2;
select * from tt2
*
ERROR at line 1:
ORA-00942: table or view does not exist
SQL> flashback table tt2 to before drop;
Flashback complete.
SQL> select count(1) from tt2;
COUNT(1)
----------
32
如果在表删除后,又新建了这个表,恢复时可以重命名,如下:
SQL> drop table tt2;
Table dropped.
SQL> flashback table tt2 to before drop
2 rename to tt2_old;
Flashback complete.
SQL> select count(1) from tt2_old;
COUNT(1)
----------
32
如果这个表删除了不止一次,我想恢复某一次的删除,怎么办?
查询recyclebin视图,或者show recyclebin,然后带名字恢复.
SQL> drop table tt2_old;
Table dropped.
SQL> show recyclebin
ORIGINAL NAME RECYCLEBIN NAME OBJECT TYPE DROP TIME
---------------- ------------------------------ ------------ -------------------
TT2_OLD BIN$SOz1cXPCADLgQwoKCiEAMg==$0 TABLE 2008-03-21:13:51:49
SQL>
SQL> create table tt2_old as select * from job;
Table created.
SQL> drop table tt2_old;
Table dropped.
SQL> show recyclebin
ORIGINAL NAME RECYCLEBIN NAME OBJECT TYPE DROP TIME
---------------- ------------------------------ ------------ -------------------
TT2_OLD BIN$SOz1cXPDADLgQwoKCiEAMg==$0 TABLE 2008-03-21:13:52:40
TT2_OLD BIN$SOz1cXPCADLgQwoKCiEAMg==$0 TABLE 2008-03-21:13:51:49
SQL> flashback table "BIN$SOz1cXPCADLgQwoKCiEAMg==$0" to before drop;
Flashback complete.
SQL> desc tt2_old
Name Null? Type
----------------------------------------- -------- ----------------------------
EMPLOYEE_ID NUMBER(4)
LAST_NAME VARCHAR2(15)
FIRST_NAME VARCHAR2(15)
MIDDLE_INITIAL VARCHAR2(1)
JOB_ID NUMBER(3)
MANAGER_ID NUMBER(4)
HIRE_DATE DATE
SALARY NUMBER(7,2)
COMMISSION NUMBER(7,2)
DEPARTMENT_ID NUMBER(2)
可以看到上述结果不是job表的结构,而是第一次时的结构
使用限制:
1 只有非系统表空间,而且是本地管理的表空间
2 表上相关对象被保留,除了以下内容:
bitmap
相关文档:
实现方法:
1、开始->设置->控制面板->管理工具->服务停止所有Oracle服务。
2、开始->程序->Oracle - OraHome81->Oracle Installation Products->Universal Installer
卸装所有Oracle产品,但Universal Installer本身不能被删除
&nb ......
--single line method
select ascii('A') Big_A from dual;
select chr(65) A, chr(122) z, chr(223) ch3 from dual;
select concat('sigo','way') from dual;
select initcap('sigoway') from dual;
select instr('ababab','a',-1,2), instr('ababab','a',1,3) from dual;
select instrb('ababab','a',1,3) from dua ......
该函数用来返回一个四舍五入后的值
SELECT ROUND( number, [ decimalplaces ] ) from DUAL
參數:
必填项:number : 要处理的数值(数值表达式)
可选项:decimalplaces : 四舍五入时取的小数的位数,不填则返回整数
Sample :
select round(123.456) from dual;& ......
http://topic.csdn.net/t/20040818/16/3287013.html
1.基本结构
CREATE OR REPLACE PROCEDURE 存储过程名字
(
参数1 IN NUMBER,
参数2 IN NUMBER
) IS|AS
变量1 INTEGER :=0;
变量2 DATE;
BEGIN
END 存储过程名字
说明:is也可换成as
2.SELECT INTO STATEMENT
& ......
left join 和 left outer join 的区别
通俗的讲:
A left join B 的连接的记录数与A表的记录数同
A right join B 的连接 ......