Shell

Hive shell command.Connect Hive ShellDirect Input Hive　1. Display tableHive> Show tables;OkTestTime taken:0.17 seconds, fetched:1 row (s)　2. Create a tableHive> CREATE TABLE Test (key string);OkTime taken:0.265 seconds3. Create partition Table:Hive>

One: Shell introduction1. What is a shellThe Shell's Chinese meaning is "shell," in layman's words, the shell is an interactive programming interface that uses the user input to drive the operating system kernel to complete the specified work. In

The shell is a bridge between command and hardware.The shell works in two ways: interactive, batch dispositionInteractive: A user enters a command at a time, the shell translates and executes aBatch processing: The user makes multiple commands into

Shell programming is in the form of:1: meta-character []. *  ?+ ( )  | {  }  ^  $2: [a-z0-9] Represents a random number and letter match3: [^a-z] matches the random one except the letter4:ab+c + represents a character that matches one or more of the

Alias creating aliasesUnalias Deleting aliasestype [name] to see if it is an internal or external commandenv lists all environment variables and their contents in the current shell environmentset to observe all variables in the current shell

Post Address: http://keep88.blog.51cto.comBo main name: Li ChangmingThis note is from------and the old boy learn Linux OPS "shell programming Combat"Directory:Core basic knowledge and practice of shell variables1. Variable type:Environment variables

The shell script resembles the following: Bash or dash The wording of a case statement Script Help notation The wording of whether the argument is empty Parameters #! /bin/Bash Case " $" inch-h|--help|?) Echo "usage:1

This article is intended to accumulate a solution to small problems that are encountered when writing shell scripts at ordinary times. There are occasional updates here for later review and continuation.One, define the default values in the shell

Demand:Text in the first column of the word typeface, and so on, the second column is added, the final output characters and the final and (for the convenience of final check, gave 1)The text is as follows:Cat test.logabc 1aaa 1bbb 1ddd 1sss 1iii

1 Batch Create users:#!/bin/bashI=30Groupadd Class2While [$i-le 50]DoIf ID user$i &>/dev/nullThenecho "This user$i is exist"ElseUseradd-g class2 user$i && echo "User$i" | passwd--stdin user$i &>/dev/null && echo "This user$i is created"Fi((i++))Done2

This is a wonderful command.TR's whole spell is translate, that is, translation. Interestingly, we are able to make rules for translation. Use methods such as the following:TR [option] set1 [Set2]TR accepts input from standard input. The results are

Python-c "Print (' + ' *100)"Head-c 100/dev/zero |awk ' gsub (/./, "+") 'Perl-le "Print (q (+) x100)"println ("+" *100)method to output 50 x = echo "" | Sed ': A; s/^/=/; /=\{50\}/b; Ta Sed ': A;s/^.\{0,49\}$/&=/;ta ' awk '

Script 1#!/bin/bashdate=$ (date +%y%m%d%h%m) name=$ (echo $1 | awk -f ', '   ' {Print NF} ') Log_path= "$" if [ $# -ne 2 ];then    echo  "USAGE: sh  $0 log_name1,log_name2 log_path "    exitfifor NUM in " seq  1  $NAME ' do    log_name=$

Recently received the manager request to the RHEL7 LVM new partition expansion automation, because uses the virtualization platform, therefore uses to add the new disk the way to do:#!/bin/bash# #在线扫描新磁盘# #Step1: Recognize New hard

1. Purpose(1) Shell knowledge Summary. Good memory is better than bad writing, finishing the relevant shell knowledge and combining their own practical experience to organize, the content will not involve all the knowledge points, will only cover

A wildcard wildcard is a class of keyboard characters. Wildcards are often used in place of one or more real characters when looking for a folder, when you don't know the true character, or if you don't want to type the full name.             *

The first is to create the shell daemon: (shouhu.sh)#!/bin/bashtest () {        while true         do                 ls ./  >> 123.txt                 sleep 5                              done}case $1 instart)         path= "/root/shouhu.pid"       

Backing up MBR, root partition, boot partition#!/bin/bashBak_dir=/mnt #已挂载的移动硬盘或其他外设Mbr= ' fdisk-l |grep ' Disk ' |awk nr==1 ' {print $} ' |awk-f '/' ' {print $} ' |sed s/://g 'root= ' df |awk '/\//{print} ' |awk nr==1 ' {print $} 'boot= ' df |awk '/

Record the use of arrays in the shellThe main is the creation of elements, elements of the increment, delete, change operation.1#!/bin/Bash2 3 #基本数组操作4A= (1 2 3) # # () denotes an empty array5 Echo "a No. 0 element:"${a[0]}6 Echo "all elements:"${a[@

The head of the Sunset Building, the voice of the hung, Jiangnan wandering. The Wu hook to see, the railing shot all over, no one will, boarding meaning. --Deng Jiankang and Heart PavilionThe hill algorithm is a sort algorithm proposed by Hill