- 浏览: 21390 次
- 性别:
- 来自: 上海
最新评论
-
metaphy:
一个不容忽视的问题是:有大厂商来推吗?
爱立信看起来应该出来推 ...
程序语言的新星:走近Erlang的世界
文章列表
Benchmark Analysis: Guice vs Spring
At the weekend I managed to get some free time away from working on our next release to look at a recent benchmark that compared the performance of Google Guice 1.0 with
- 2009-01-04 23:31
- 浏览 1409
- 评论(0)
The need for performance metrics and comparison
Since we released AspectWerkz 1.0, and more generally for every release of any AOP / interceptor framework (AspectWerkz, AspectJ, JBoss AOP, Spring AOP, cglib, dynaop etc), a question is always raised: "what is the performance cost of such an appro ...
- 2009-01-04 23:20
- 浏览 1149
- 评论(0)
http://www.ibm.com/developerworks/java/library/j-genericdao.html
- 2008-11-22 12:02
- 浏览 1004
- 评论(0)
iBATIS, Hibernate, and JPA: Which is right for you?
Object-relational mapping solutions compared
original site:http://www.javaworld.com/javaworld/jw-07-2008/jw-07-orm-comparison.html?page=5
By K. L. Nitin, Ananya S., Mahalakshmi K., and S. Sangeetha, JavaWorld.com, 07/15/08
Object-relational mappi ...
- 2008-08-28 14:34
- 浏览 3339
- 评论(0)
How do you become an expert?
The answer is the same in all the fields I've seen:
Andrew Koenig
1. Learn the basics.
2. Study the same material again - but this time , concentrate on the details you didn't realize were important the first time around.
- 2008-07-01 11:29
- 浏览 921
- 评论(0)
提起Erlang语言,相信许多人都会挠头,因为它实在是太陌生了。在2007年6月由TIOBE Programming Community提供的程序语言排名中,Erlang占有率仅为0.08%,排名第49位。与之形成鲜明对比的是,Java以20.025%的占有率高居榜首,紧随其后 ...
- 2008-06-13 12:43
- 浏览 1971
- 评论(1)
C和C++里面的lvalue 和 rvalue的释义
在看GCC的文档的时候,看到一个词lvalue,查了金山词霸其释义为 lvalue [计] 左值。因为的确在介绍编译原理的课程中听过这个词,大致知道其意思就没有多想。但是看完GCC文档的这个篇幅,都无法明白全篇在说什么。问题还是出在了lvalue这个词的“左值”是什么意思的理解上了。再找M-W字典,却告知没有这个词。于是google了一把,的确很多地方都称其为左值,我仍然不得要领。最后在一个百科网站About Site上找到该词的准确释义,摘贴如下:Definition: C and C++ have the notion of lvalue ...
- 2008-06-08 17:14
- 浏览 1559
- 评论(0)
From:http://blog.csdn.net/luyang1016/archive/2007/09/10/1778862.aspx (原创:闭月羞花猫 2007/09/10) 前一段时间对工作,对未来一直很迷茫。并在这期间,陆续的发表了一些文章。在这一段时间,几乎对软件生产失去了信心,对程序员的 ...
- 2008-05-24 11:42
- 浏览 1217
- 评论(0)
互联网的主要模式
一、网络门户
所谓网络门户就是进入因特网的大门,它具备强大的信息检索信息交流和信息传递功能,有综合性门户和垂直门户之分,广告是他们主要的收入来源。
1.雅虎(YAHOO)和美国在线(AOL):华 ...
- 2008-05-24 11:33
- 浏览 1272
- 评论(0)
oracle如何实现:每天统计前面几天销售额的总额
- 博客分类:
- DB
用分析函数 统计某商店的营业额。
date sale
1 20
2 15
3 14
4 18
5 30
规则:按天统计:每天都统计前面几天的总额
得到的结果:
DATE SALE SUM
----- -------- ------
1 20 20 --1天
2 15 35 --1天+2天 ...
Oracle中ROWNUM的使用技巧
作者: fuyuncat
来源: www.HelloDBA.com
ROWNUM是一种伪列,它会根据返回记录生成一个序列化的数字。利用ROWNUM,我们可以生产一些原先难以实现的结果输出,但因为它是伪列的这个特殊性,我们在使用时也需要注意一些事项,不要掉入“陷阱”。下面就介绍一下它的使用技巧及注意事项。
1 特殊结果输出
利用ROWNUM,我们可以做到一些特殊方式的输出。
1.1 Top N结果输出
我们如果希望取输出结果的前面几条数据,通过ROWNUM可以轻松实现:
SQL> select * from t_t ...
- 2008-05-15 10:52
- 浏览 1869
- 评论(0)
ROWNUM
For each row returned by a query, the ROWNUM pseudocolumn returns a number indicating the order in which Oracle selects the row from a table or set of joined rows. The first row selected has a ROWNUM of 1, the second has 2, and so on.
You can use ROWNUM to limit the number of rows returned by ...
- 2008-05-15 09:35
- 浏览 1496
- 评论(0)
Welcome to the Seasar Project!
Today, Dependency-Injection is the most popular technology of Java. However, did it make our development work really easy? You must be still irritated with writing configuration files. Seasar2, the most popular open source framework in Japan, frees you from such annoya ...
- 2008-05-07 13:30
- 浏览 1293
- 评论(0)