直接上代码: List<Student> ss = new List<Student>(); Student ss1 = , Age = , Name = " }; Student ss2 = , Age = , Name = " }; Student ss3 = , Age = , Name = " }; Student ss4 = , Age = , Name = " }; Student ss5 = , Age = , Name = &
#!bin/bash#作者:liusingbon#功能:统计 Linux 进程相关数量信息,running(运行的进程),sleeping(睡眠中的进程),stoped(停止的进程),zombie(僵尸进程)running=0sleeping=0stoped=0zombie=0#在 proc 目录下所有以数字开始的都是当前计算机正在运行的进程的进程 PID#每个PID编号的目录下记录有该进程相关的信息for pid in /proc/[1-9]*doprocs=$[procs+1]stat=$(
删除df中任意字段等于'null'字符串的行: df=df.astype(str)#把df所有元素转为str类型 df=df[df['A'].isin(['null','NULL'])] #找出df的'A'列值为'null'或'NULL'(注意此处的null是字符串,不是空值) df=df[~df['A'].isin(['null','NULL'])] #过滤掉A列为'null'或'NULL'的行,~表示取反 去掉任意一列为'null'值的行,目前只能想到用循环: for col in list
1.统计每分钟内 url 的访问数量 SELECT SUBSTRING(CONVERT(varchar(100), date, 20), 0,17) as dateTime,COUNT(url) as count,url,referer FROM demo GROUP BY url,(SUBSTRING(CONVERT(varchar(100), date, 20), 0,17) ),referer;
update a left join c on a.id = c.id set a.body = c.c1 where a.id=c.id; update zcat as z left join zcat_bak_1212 as zb on z.zcatId = zb.zcatId set z.zcatName = zb.zcatName where z.zcatName is null;
1.可以使用count SELECT count(name='A' OR NULL) FROM table 2.用sum SELECT sum(if( = 'A', 1, 0)) FROM table 以上只是简单的方式,如遇到复杂的多表查询,可以结合GROUP BY,count() or sum()函数得出对应数据
Given a sequence of n numbers a1, a2, ..., an and a number of d-queries. A d-query is a pair (i, j) (1 ≤ i ≤ j ≤ n). For each d-query (i, j), you have to return the number of distinct elements in the subsequence ai, ai+1, ..., aj. Input Line 1: n (1
#!/usr/bin/python #-*- coding: utf- -*- import os import re rawfile = '/var/log/auth.log' def rawparse(rawfile): ipdict = {} fhandle = open(rawfile,'r') regexp = re.compile('\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}') for line in fhandle: result = regexp.fi