Posted by dbtan on 12月 19th, 2016 通过上篇文章,我们已经基本了解 标记列为未使用 (Marking Columns Unused) 了。
我们知道,在 SET UNUSED 后 其实数据并未真的被删除,若这时又想恢复该列,有办法吗?
接下来,我们来实验一下。
如何修复被标记为 UNUSED 的字段
0. 实验环境 Oracle 11.2.0.4 SQL 16:49:06 [email protected](tq-78)> select * from v$versio
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Posted by dbtan on 12月 16th, 2016 Marking Columns Unused 基本操作步骤
1. 标记列为未使用 SQL ALTER TABLE <table_name> SET UNUSED (<column_name>);
2. 然后在数据库空闲时,再删除列 SQL ALTER TABLE <table_name> DROP UNUSED COLUMNS CHECKPOINT <n>; -- CHECKPOINT <n>
In the ALTER TABLE statement that fo
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Posted by dbtan on 9月 15th, 2010 How To Automate Cleanup Of Dead Connections And INACTIVE Sessions [ID 206007.1] Modified 25-JUN-2009 Type HOWTO Status PUBLISHED
PURPOSE
------- This note explains the difference between a dead connection and an
INACTIVE session in v$session
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Posted by dbtan on 9月 26th, 2009 今天为开发数据库导入数据,使用sqlloader。记录一下遇到的问题及笔记。
1、表结构如下: [email protected]> desc member_actions;
Name Null? Type
----------------- -------- ------------
PHONE NOT NULL VARCHAR2(50)
ACTION_TIME NOT NULL DATE
URL
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Posted by dbtan on 9月 14th, 2009 注:我的实验环境是RHEL5.3(64bit) + Oracle11gR1(11.1.0.6)(64bit) [[email protected]: ~]#uname -a
Linux test7 2.6.18-128.el5 #1 SMP Wed Dec 17 11:41:38 EST 2008 x86_64 x86_64 x86_64 GNU/Linux [email protected]> select * from v$version; BANNER
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