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Yesterday to Anhui Susong a customer there to maintain the experience and lessons The client's database server would have been good, and I was able to demonstrate to others how to install Oracle clients, install Oracle clients on the server, and halfway through the installation I suddenly felt I had found a great error: Oracle server could no longer install Oracle clients, I quit but it's too late: fee management system can not connect to the databas

:::22 :::* listen922/sshdtcp6 00::1:25 :::* listen1031/mastertcp60 0:::3306 :::* listen1667/mysqld If the template/etc/my.cnf is not configured, use the command line method:[[Emailprotected]mysql]#servicemysqldstopshuttingdownmysql]. success! [[Emailprotected]mysql]#/usr/local/mysql/bin/mysqld_safe--defaults-file=/etc/my.cnf --user=mysql--datadir=/data/mysql[1]1848[[emailprotected]mysql]# 18013122:45:06mysqld_safeLoggingto '/data/mysql/localhost.localdomain.err '. 18013122:45:06mysqld_safest

the where clause having . You can use exist and not exist instead of In and not. You can use table links instead of exist. Having can be replaced by where , if not replaced, can be handled in two steps. Example SELECT * from ORDERS WHERE customer_name not in (SELECT customer_name from CUSTOMER) Optimized SELECT * from ORDERS WHERE customer_name not exist (SELECT customer_name from CUSTOMER) 7.2 do not declare numbers in character format, you want to declare character values in numeri

database version select version ();• View database status show status;(data not all shown)• View each parameter show variables; Show variables like ' max_connect% ';Show variables;(Too many parameters)• Modify parameter set global max_connect_errors=1000;If you want to permanently take effect, you need to exit to SHELL,VIM/ETC/MY.CNF, define max_connect_errors=1000;• View queue show processlist; Show full processlist;If there are errors, please correct, learn from each other and progress togeth

rows affected (0.01 sec)• Completely delete the database:Drop database db1;mysql> drop Database db1; Query OK, 1 row affected (0.01 sec) 13.6 MySQL Database backup recovery• Backup library:Mysqldump-u User name-p password Database > backup data file path[Email protected] ~]# mysqldump-uroot-p123456 mysql >/tmp/mysql.sql(Too much data is not listed)• Recovery library:Mysql-u User name-p password Database [Email protected] ~]# mysql-uroot-p123456 MYSQL2 • Backup table:Mysqldump-u Use

the WHERE clause is used in the inch , not in , or or having . can use exist and the Not exist Replace inch and the not in . You can use table links instead exist . Having can be replaced by where , if not replaced, can be handled in two steps. ExampleSELECT * from ORDERS WHERE customer_name not in(SELECT customer_name from CUSTOMER)Optimized SELECT * from ORDERS WHERE customer_name not exist(SELECT customer_name from CUSTOMER)7.2 do not declare numbers in character format, you want to dec

10.28 Rsync Tools IntroductionThe file Synchronization tool rsync, can achieve incremental copy, CP is direct coverage, low efficiency;Install rsync, #yum-y install rsync;Rsync Common methods,Copy the passwd file to the/tmp directory, rename it to 1.txt, and the command to #rsync-av/etc/passwd/tmp/1.txt-V visualization;Remote copy, command for #rsync-av/etc/passwd [email protected]:/tmp/1.txt; then enter the password;10.29/10.30 rsync Common Options10.31 rsync sync via ssh-e Specifies the port,

14 weeks four sessions (May 14)16.1 Tomcat Introduction16.2 Installing the JDK16.3 Installing Tomcat16.1 Tomcat Introduction16.2 Installing the JDKOpen the download URL.Click jdk=8u144-linux-x64.tar.gz, downloadUpload to LinuxCtrl+f Open XftpPut the downloaded file in the root directoryXftp is an SSH-based port that does not require FTP to be opened.CopyAt the bottom, pasteCheck to see if the installation is successful, the following results appear, stating that there is no problem, the command

();-------------------------------------------------------------------curl-x127.0.0.1:80 test.com/upload/3.php //Can not parse, directly to the source code (written content) display/usr/local/nginx/sbin/nginx-t/usr/local/nginx/sbin/nginx-s Reloadcurl-x127.0.0.1:80 test.com/upload/3.php //Normal parsingTail/usr/local/nginx/logs/error.log//View error log12.16 Nginx AgentCd/usr/local/nginx/conf/vhostVim proxy.conf//Add the following:-----------------------------------------------------------------

Tags: Linux notes12 weeks three sessions (April 25)12.10 Nginx Access Log12.11 Nginx Log Cutting12.12 static files do not log logs and expire time12.10 Nginx Access LogThe format of the configuration file is in the main configuration file.Search for log to find the following paragraph, which is used to define the format.Public network IP, in Baidu, search IP, view.Defining Access Log pathsOpen FileUnder}, add a row to read as follows:12.11 Nginx Log CuttingEdit FileAdd the following contentProce

= ' date-d '-1 day +%y%m%d '//similar to 20180427, yesterday's date, today 28thLogdir= "/data/logs"Nginx_pid= "/usr/local/nginx/logs/nginx.pid"CD $logdirFor log in ' ls *.log 'DoMV $log $log-$dDone/bin/kill-hup ' Cat $nginx _pid '--------------------------------------------------------------------------------------Add Task Schedule #crontab-e//write the following:0 0 * * */bin/bash/usr/local/sbin/nginx_logrotate.sh//Daily 0 o'clock in the morning execution12.12 static files do not log logs and e

This class, this semester we have only one of the three departments of this course, many many many students say why you have to choose this course. Parents also say, why don't you come with the crowd. Someone asked me before, whether regrets chose such a class, I said, regret. This course, which requires self-study and my student work, almost fills my own leisurely junior. Said regret that Thursday, I still for Lou big exam struggle, scratching the scalp, bite broken fingers, restless. Now, this

Tags: LinuxSeven weeks Five sessions (March 23)10.19 iptables Regular backup and recovery10.20 Firewalld 9 Zone10.21 Firewalld About zone operation10.22 Firewalld about service operations10.19 iptables Regular backup and recoveryBackup, command as followsIptables rules can be backed up to other files, and the file name can be taken by itself.Only the rules for NAT.There are no rules in this tableBack up the rules just nowIf you want to restart, load, you need to put in the configuration file, to

the data has been mistakenly deleted, the first thing to do is to unload the partition of the deleted data, if the data of the root partition is mistakenly deleted, you need to enter the system into single user mode, and the root partition is mounted in read-only mode. Since the file is deleted, only the sector pointer in the Inode node of the file is zeroed out, the actual file is also stored on disk, and if the disk continues to mount in read-write mode, the data blocks of these deleted file

While loopThe process is as followsWhile condition:code blockKey words1 break is used to end the sequence, the following code is not executing2 Continue is used to jump out of this sequentialExample output 1-100 or less all positive integersThe code is as followsS1 = 1While True:Print (S1)if S1 = = 100:BreakS1 + = 1Example of cumulative sum of output 1-100Analysis, 1 now implements a positive integer of output 1-100B1 = 0S1 = 1While True:Print (S1)B1 = B1 + S1if S1 = = 100:BreakS1 + = 1Print (B1

=" Http://s1.51cto.com/wyfs02/M00/89/21/wKioL1gIw6Chq1kGAAD7pY2B3No086.jpg-wh_500x0-wm_3 -wmp_4-s_1235337174.jpg "Title=" mount. JPG "alt=" Wkiol1giw6chq1kgaad7py2b3no086.jpg-wh_50 "/>Then enter the rescue mode, found that the rescue mode will not enter.650) this.width=650; "Src=" Http://s2.51cto.com/wyfs02/M01/89/21/wKioL1gIw-XgbK5wAADA8r-78zg027.jpg-wh_500x0-wm_3 -wmp_4-s_2478663793.jpg "title=" output. JPG "alt=" Wkiol1giw-xgbk5waada8r-78zg027.jpg-wh_50 "/>The whole place, feel the collapse,

Write a function that meets the following requirements:A) Calculates the result of printing all parameters and multiplying the cardinality (base=3)b) If the last argument in the parameter is (base=5), the cardinality is set to 5, and the cardinality does not participate in the sum calculation.#-*-Coding Utf-8-*-def results (*i): sum=0 for J in I: sum + = J if I[len (i) -1]==5: c10/>sum= (sum-5) sum*=5 else: sum*=3 return Sumprint (results (1,2,3,4,5)) Little Turtle Python cou

single line, it is not equivalent to a C or C + + inline function, which is designed to call small functions without consuming stack memory to increase operational efficiency.Example:#!/usr/bin/python#-*-Coding:utf-8-*-# Writable Function Descriptionsum = lambda arg1, arg2:arg1 + arg2;# Call the SUM functionPrint "added value is:", SUM (10, 20)Print "added value is:", SUM (20, 20)Built-in functions:Common functions:ABS ()Max ()Min ()Len ()Divmod ()POW ()Round ()Callable ()Type ()Isinstance ()CM

above, the data is not accurate.If you want to avoid this situation, just use get and CAS, such as:#!/usr/bin/env python#-*-Coding:utf-8-*-#Author: Haifeng DiImport MemcacheMC = Memcache. Client ([' 192.168.10.128:12000 '], debug=true)v = mc.gets (' Product_count ')Print (v)#如果有人在gets之后和cas之前修改了product_count, the following setting will fail to throw an exception to avoid output of abnormal dataV1 = Mc.cas (' Product_count ', "899")Print (v1)#结果:899TrueIn essence, each time the get is executed,

while loop.The break statement terminates the Loop statement, that is, the loop condition does not have a false condition, or the sequence is not fully recursive, and the loop statement is stopped.The break statement is used in the while and for loops.If you use a nested loop, the break statement stops executing the deepest loop and starts executing the next line of code.The Python continue statement jumps out of the loop, and break jumps out of the loop.The continue statement is used to tell P