jiangduxi
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最新评论
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snow8261：
太粗略了。
企业架构之数据架构 -
haithink：
面试成功没？
JVM 加载Class文件的原理及其机制 -
feisi0003731843：
不好意思我没有重启，重启后好多了，可有的地方回放还是不成功的。 ...
Selenium IDE测试ExtJs一种测试解决办法 -
feisi0003731843：
这个好像不行吧，我试过了不好使啊。还是用id来做的。不能用啊。 ...
Selenium IDE测试ExtJs一种测试解决办法 -
yuchensuifeng：
您好，静态页面是可以的，但是，我指定error-page为js ...
JSP创建错误处理页面
文章列表
当今软件系统行业中，软件架构决定了，软件的好坏。就好比人等骨架，如果人等骨架都不好，那么人也很脆弱。软件架构这个在软件工程领域将是一个永恒的话题。随着软件行业的高速发展，现在国际软件工程界在软件架构 ...
理解Use Case和Actor
Use Case 可以促进与用户沟通，理解正确的需求，另外可以划分系统与外部实体的界限，是系统设计的起点，而最终应该落实到类和实现代码上。
Use Case View与Logical View 应该有明确的相关性，UML从Use Case到类包的关联可以用到依赖/实现关系描述
Actor不一定指人，而是指代表某一中特定功能的角色，因此同一个人可能对应很多个Actor。Actor是个虚拟的概念，也可以指外部系统和设备
Use Case是对系统行为的动态描述，它是OO设计的起点，类，对象，操作的来源，通过逻辑视图的设计，可以获得软件的静态结构。
UML中的 ...
Use Case （使用案例）：在一般的UML建模过程中，分为以下几个阶段：业务、需求、分析和设计，其中设计可分为结构分析和行为分析。业务是对商业模型的深刻理解，从商业模型里面提取出业务需求，然后把需求分解成一系列的 ...
Here are a few simple suggestions to help you improve your learning abilities.
We are a nation overloaded with information.So many new things are thrown at us that we need to learn and remember that it becomes overwhelming. In our fast paced world here are a few tips that will help us accelerate ...
1、定期分析表和检查表
分析表的语法如下：
引用
ANALYZE [LOCAL | NO_WRITE_TO_BINLOG] TABLE tb1_name[, tbl_name]...
以上语句用于分析和存储表的关键字分布，分析的结果将可以使得系统得到准确的统计信息，使得SQL能够生成正确的执行计划。如果用户感觉实际执行计划并不是预期的执行计划，执行一次分析表可能会解决问题。在分析期间，使用一个读取锁定对表进行锁定。这对于MyISAM，DBD和InnoDB表有作用。
例如分析一个数据表
引用
analyze table table_name
检查表的语法如下 ...
What would you do if you only had a short time to live?
It's hard, from within the storm of every day life, to see things with real perspective, to know what's important and what's simply pressing on our consciousness right now,demanding attention.
We have people emailing us for information and ...
一般在数据中，很多朋友很喜欢用索引来对数据库优化。通过索引通常可以帮助我们解决大多数的SQL性能问题。
1. 索引的存储分类
MyISAM存储引擎的表的数据和索引时自动分开存储的，各自是独立的一个文件；InnoDB存储引擎的表的数据和索引时存储在同一表空间里面，但可以有多个文件组成。
MySQL中索引的存储类型目前只有两种(BTREE和HASH),具体和表的存储引擎相关；MyISAM和InnoDB存储引擎都只支持BTREE索引；MEMORY/HEAP存储引擎可以支持HASH和BTREE索引。
MySQL目前不支持函数索引，但是能对列的前面某一部分进行索引，例如name字 ...
I placed the small bottle labeled"Club Soda"on the floor, in front of the shrink.
"What's this?"She asked.
"This,is vodka,"I replied."Let me tell you a story about it."
"Once upon a time, a girl went to school at Fort River. She was in sixth grade, ...
一般使用SQL的时候你是不会去想到优化。但是面对一个有SQL性能问题的数据库时，我们应该如何入手进行系统的分析，使得能够尽快定位问题SQL，并且尽快解决问题。
1.使用show status 命令了解各种SQL的执行频率
引用
例如在Mysql的Cline上输入
show status like 'Com_%';
显示的是一些:Com_xxx.
Com_xxx 表示每个xx语句执行的次数。通常情况下我们比较关注如下一些操作：
引用
Com_select:执行select操作的次数
Com_insert:执行Insert操作的次数，对于批量插入的INSERT操作，只累加一 ...
In at least one respect, I'm not a typical expatriate teacher of English. Many-perhaps most-of us make out careers teaching overseas. I came out here after many years of teaching and teacher training in England only three ago, so I'm still relatively a newcomer. And of course I make comparisons. Of ...
I recently spoke to a class of high school freshmen in Houston about the value of a college education and avoiding the pitfalls that so many men of color seem incapable of doing.
Many times speaking to inner-city youth can be a daunting task because they do not see the opportunities that many midd ...
Often we're told that we have to suffer now -- give up what we want -- in order to succeed later, that in order to save we must sacrifice. Give up instant gratification to get delayed gratification.
But you can do both.
For years, I was confused about this, as I read books and websites that sen ...
In order to experience everlasting love in life, you ought to first figure out what is missing in your life and then fill in the gaps. People fall in in and out of love because they expect their lovers to be everything to them and do everything for them. They then become dissatisfied when the partn ...
Far from the Beijing Olympics and far from the Sichuan earthquake is another China -- one that hasn't been bulldonzed and rebuilt in anticipation of the Games and one that won't be transformed by their glamour. It's a China that is long past but glimpsed in three remote and astonishingly well-preserv ...
There are some people who are completely happy with themselves, their lives, and their prospects for the future. While they can be considered to be more fortunate than most, most who do not fall into that category are not as bad off as they tend to believe. Instead, they are simply lcaking somethin ...