关闭数据库(援引Oracle联机文档)
Close a Database
When you close a database, Oracle writes all database data and recovery data in the SGA to the datafiles and redo log files, respectively. Next, Oracle closes all online datafiles and redo log files. (Any offline datafiles of any offline tablespaces have been closed already. If you subsequently reopen the database, any tablespace that was offline and its datafiles remain offline and closed, respectively.) At this point, the database is closed and inaccessible for normal operations. The control files remain open after a database is closed but still mounted.
Close the Database by Terminating the Instance
In rare emergency situations, you can terminate the instance of an open database to close and completely shut down the database instantaneously. This process is fast, because the operation of writing all data in the buffers of the SGA to the datafiles and redo log files is skipped. The subsequent reopening of the database requires recovery, which Oracle performs automatically.
Note:
If a system or power failure occurs while the database is open, then the instance is, in effect, terminated, and recovery is performed when the database is reopened.
Unmount a Database
After the database is closed, Oracle unmounts the database to disassociate it from the instance. At this point, the instance remains in the memory of your computer.
After a database is unmounted, Oracle closes the control files of the database.
Shut Down an Instance
The final step in database shutdown is shutting down the instance. When you shut down an instance, the SGA is removed from memory and the background processes are terminated.
Abnormal Instance Shutdown
In unusual circumstances, shutdown of an instance might not occur cleanly; all memory structures might not be removed from memory or one of the background processes might not be terminated. When remnants of a previous instance exist, a subsequent instance startup most likely will fail. In such situations, the database a
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虽然学习Java很久了，自己也连接过一些数据库，比如mysql之类的，如今呢，也学习了一段时间的Oracle，然而呢，今天是我第一次连接Oracle，嘿嘿，应该还不算太迟吧。
今天呢，有点笨拙，大家莫笑！
我这是一个查询例子
首先，� ......
学习Oracle DBA也半个多学期了，今天猛然才发现，原来我的书还是很新的，上课操作时候也只是知道大概怎么做，但是要真的全部自己做，而不去翻书还是有一定的难度的，所以呢，今天开始将DBA从头复习一遍，同时再操作一遍。
第一章，学的是Oracle的体系结构� ......
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
变量1 INTEGER :=0;
变量2 DATE;
BEGIN
END 存储过程名字
2.SELECT INTO STATEMENT
将select查询的结果存入到变量中，可以同时将多个列存储多个变量中，必须有一� ......
今天在百度上搜索了下oracle写的触发器，感觉还可以。
就收藏咯。
用户表：创建触发器之前首先要创建序列
用户表序列：
create sequence users_seq;
用户表触发器：
create or replace trigger bifer_users_userid_pk
before insert
on users
for each row
begin
select users_seq.nextval into:new.userid from ......
<一>实现杀死某个用户的客户端连接进程
1.以管理员身份登录后查看V$SESSION的视图结构
SQL> desc v$session;
名称 &n ......
