这个是jrlee在帖子中转载的关于dual的东西 看看这个可以对dual有个更深入的了解 [quote]原帖由 "jrlee" 发表: 神秘的dual black_snail(原作) 关键字 ORACLE dual dual ? 有什么神秘的? 当你想得到ORACLE系统时间, 简简单单敲一行SQL 不就得了吗? 故弄玄虚…. SQL>; select sysdate from dual; SYSDATE --------- 28-SEP-03 哈哈, 确实dual的使用很方便. 但是大家知道dual倒底是什么OBJECT, 它有什么特殊的行...
octupus,LAam安装文档 此文档找来后自己按着做..结果我的am版本.只支持.redhat as2.1不过还是贴上来了.均为转载. 一、Legto Octupus的安装 REPLISTOR (Octopus) 安装测试 一、 硬件要求: 从机(Target)的硬盘具有足够的剩余空间与主机(Source)需要镜像的目录以及其文件变化量大小相当。建议选用一对相同的100M网卡分别插在主机和从机上,用一条正牌五类或以上的级连线直连,作为可选专用连接。(级连线接法:1、2 对...
Table - `dual`:a dummy table in mysql mysql文档中对于dual表的解释: You are allowed to specify dual as a dummy table name in situations where no tables are referenced: mysql> SELECT 1 + 1 FROM dual; -> 2 dual is purely for the convenience of people who require that all SELECT statements should have FROM and possibly other clauses. MySQL may ignore the c...
Design Considerations There are two separate considerations when using two Internet uplinks: Link Redundancy and Load Sharing. These two features can be combined or implemented separately. Scenario Link Redundancy Load Sharing 1 Yes No 2 No Yes 3 Yes Yes In each scenario, you must configure the appropriate firewall policies between the interfaces in question to allow the traffic - this document f...