语法:ROW_NUMBER() OVER(PARTITION BY COLUMN ORDER BY COLUMN)简单的说row_number()从1开始,为每一条分组记录返回一个数字,这里的ROW_NUMBER() OVER (ORDER BY xlh DESC) 是先把xlh列降序,再为降序以后...
分类:
数据库 时间:
2014-06-28 18:08:45
阅读次数:
574
设计模式总结(3)==========================================singleton pattern单件模式:确保一个类只有一个实例,并提供一个全局访问点。线程安全:同步getInstance方法:public synchronized static Single...
分类:
其他好文 时间:
2014-06-28 16:31:15
阅读次数:
299
BACKGROUNDA single physical platform may be segregated into a plurality of virtual networks. Here, the physical platform incorporates at least one vir...
分类:
移动开发 时间:
2014-06-28 14:46:39
阅读次数:
330
You are given two linked lists representing two non-negative numbers. The digits are stored in reverse order and each of their nodes contain a single ...
分类:
其他好文 时间:
2014-06-28 14:31:12
阅读次数:
201
Given an array of integers, every element appears three times except for one. Find that single one.Note:Your algorithm should have a linear runtime co...
分类:
其他好文 时间:
2014-06-28 13:44:09
阅读次数:
188
1.if语句(python中没有switch语句,可用if……elif……else代替)格式: if 表达式: #语句 else: #语句eg:number = 23guess = int(raw_input('Enter an integer:'))if guess == numb...
分类:
编程语言 时间:
2014-06-28 11:35:24
阅读次数:
253
SET STATISTICS TIME ON记录查询的相关数据生成随机GuidSELECT NewID()按照某一列排序并生成序号select Row_Number() OVER (ORDER BY Name) [Index] ,Name,ID ,NewID() RandomCod...
分类:
数据库 时间:
2014-06-28 11:05:19
阅读次数:
266
在官方文档ns-3-manual.pdf中,整个框架图:v 随机变量伪随机生成器pseudo-random number generator (PRNG)。默认情况下,ns-3仿真程序使用固定种子和运行数字,它们分别存在全局变量g_rngSeed 和 g_rngRun中,在ns-3.14版本以后,n...
分类:
其他好文 时间:
2014-06-28 11:01:09
阅读次数:
364
Bonding is aggregation multiple links to single link in order to increase throughput and achieve redundancy in case one of links fails. At least, offi...
分类:
其他好文 时间:
2014-06-24 10:28:42
阅读次数:
211
显示行号:Window->Preferences->Gerenal->Editors->Text Editors然后在show line number上打对勾自动提示:Window->Preferences->java->Editor->Cintent Assist->Auto activation...
分类:
系统相关 时间:
2014-06-24 09:00:40
阅读次数:
309