Shulou(Shulou.com)06/01 Report--

Common problems encountered in databases:

1. Upward expansion of scale up (personal hardware expansion) disadvantage: easy to reach the limit

two。 Expand scale out outward (the number of computers, grouped into clusters)

Moore's Law: every 18 months, the technology of the chip doubles, the price doubles, and the volume doubles.

Master-slave implementation of mysql:

High availability architecture diagram of enterprise database:

Mysql's built-in replication function is the basis for building large, high-performance applications.

Characteristics of mysql replication:

* how to copy mysql:

Master-slave replication of mysql is asynchronous.

Binlog binary log

Dump: a thread in the main mysql that sets the binary log

Icano thread: pull binaries on the main mysql and record them in relaylog

SQL thread: pull the log contents from relaylog and write to the database

Master-slave replication of mysql solves the problem of high availability

Actual combat exercise:

Master-Slave implementation of mysql

Master: vim / etc/my.cnf server-id=1 gives the server a unique ID number log_bin=mysql-bin opens binary file skip-name-resolve name resolution hostname mysql-master modifies hostname systemctl start mariadb cd / var/lib/mysql ls to check whether binary logs are generated mysql- uroot-p > GRANT REPLICATION SLAVE,REPLICATION CLIENT ON *. * TO slave@'172.17./%.%' IDENTIFIED BY 'magedu' Authorize / / > flush tables with read lock to lock / / > unlocak tables unlock the table > create database magedu; > use magedu; > create table M26 (id int not null,name char (20)); > show create table M26\ G; > insert into M26 values; > show binlog events; > show master status

From:

Vim / etc/mysql server-id=2 relay-log=mysql-relay-bin read_only = 1 log_bin = mysql-bin log_slave_updates=1 systemctl start mariadb cd / var/lib/mysql ls to see if a binary log is generated before starting the replication thread Specify the configuration of the server mysql- uroot-p > CHANGE MASTER TO MASTER_HOST='172.17.0.159', MASTER_USER='SLAVE', MASTER_PASSWORD='magedu', MASTER_LOG_FILE='mysql-bin.000001', MASTER_LOG_POS=811 > start slave; > show tabless; > create tables M27 (id int not null,name char (20)); insert table on slave server > select * from M26

Show slave status\ G to see if it is successful

Implement the master-slave architecture:

The slave node needs to open the binary log, and the master-slave architecture can be built.

Mysql replication filter: limited to one or more data-related data, not all, carried out by the replication filter

What is self-growing ID:

What is a primary key: there are several attributes in a record in relational data. If one of the attribute groups (note that it is a group) can uniquely identify a record, the attribute group can become a primary key.

The function of primary key: 1. Can guarantee the uniqueness of the data, will not produce redundant data 2. It can speed up the operation of data.

Foreign keys: used for linked list query

Index: it is a collection of one or more column values in a table and a corresponding list of logical pointers to the data pages that physically identify these values in the table

The function of index is to help query data quickly.

Mysql master and slave each other:

1.vim / etc/my.cnf server-id=1 skip-name-resolve relay-log=mysql-relay-bin log-bin=mysql-bin log_slave_updates=1 auto_increment_increment=2 auto_increment_offset=1 # replicate_do_db=magedu systemctl restart mariadb mysql- uroot-p > show databases > show master status > CHANGE MASTER TO MASTER_HOST='172.17.0.170', MASTER_USER='SLAVE', MASTER_PASSWORD='magedu', MASTER_LOG_FILE='mysql-bin.000001', MASTER_LOG_POS=245; > start slave; > show slave status; > use magedu > create table userinfo (id int PRIMARY KEY AUTO_INCREMENT, name varchar (50) NOT NULL); > show tables; > desc userinfo View table > insert into userinfo (name) value ('xiao'), (' da'), ('lao'); > select * from userinfo; 2.vim / etc/my.cnf server-id=2 relay-log=mysql-relay-bin log-bin=mysql-bin log_:wqslave_updates=1 auto_increment_increment=2 auto_increment_offset=2 # replicate_do_db=magedu systemctl restart mariadb mysql- uroot-p > show databases > show slave status\ G > CHANGE MASTER TO MASTER_HOST='172.17.0.159', MASTER_USER='SLAVE', MASTER_PASSWORD='magedu', MASTER_LOG_FILE='mysql-bin.000002', MASTER_LOG_POS=245; > start slave; > show slave status; > use magedu; > show tables; > insert into userinfo (name) value ('ni'), (' wo'), ('ta'); > select * from userinfo

Semi-synchronous replication: operations based on mutual master-slave replication

Primary node:

1. > INSTALL PLUGIN rpl_semi_sync_master SONAME 'semisync_master.so'; > SHOW GLOBA VARIABLES LIKE' rpl_semi%'; > set global rpl_semi_sync_master_enabled = 1; > stop slave; > start slave; cd / var/lib/mysql cd / var/log/mariadb tail-200mariadb.log View Log 2. > INSTALL PLUGIN rpl_semi_sync_master SONAME 'semisync_slave.so' > SHOW GLOBA VARIABLES LIKE 'rpl_semi%'; > set global rpl_semi_sync_master_enabled = 1

MHA for mysql High availability Architecture:

1. Install and configure MHA

two。 Prepare the communication environment based on SSH mutual trust

3. Install the package to install yum install mha4mysql. It is also necessary to install ode package on ftp.

4. Initialize MHA for configuration

What are the benefits of mysql master-slave replication technology: improved performance and high availability

Icano thread and SQL thread

Introduction to ysql read-write separation, sub-library, sub-table and optimization

Select for update

Middleware: mysql proxy implements the proxy of mysql, one proxy (proxy of mysql) aliSQL proxySQL

Dynamic request: php-- > server node1

Static request: css images js html-- > server node2

Sub-database sub-table:

1. Horizontal split

two。 Vertical split

Mysql Optimization:

1. You can use data to cache common memcached

two。 There are many caching mechanisms in the database, and the corresponding caching strategy can be used.

3. For data, use indexes whenever possible

4. As far as requests are concerned, read-write separation can be achieved and load balancing of read requests can be achieved.

5. For a large database, we can divide the database and table according to the business logic.

6. All optimizations are stored in memory as much as possible

Tomcat and servlet

Programming language classification:

Hardware level: microcode programming, assembly language

System level: C Cosmopolitan. (C language has high performance)

Application level: JAVA,PHP,Python,Ruby,Perl,C#,.

Object-oriented: an object is an abstract description of things

Process-oriented: operate step by step according to the order in which things develop

JAVA uses object-oriented system design method, and JAVA can implement multi-tier architecture. For large-scale enterprise applications across platforms, JAVA has almost become the only choice.

PHP:PHP is suitable for rapid development, small and medium-sized application systems, low development cost and fast response to changing needs.

JAVA compiler (bytecode)-"virtual machine (interpreter) -" interpreter (translation)-"machine code"

.java-> .class-> machine code

How JAVA works:

Programming language compilation types can be roughly divided into three types:

1. Source code-compiler-native code-run

two。 Source code-interpreter-native code-run

3. Source code-intermediate language-virtual machine (equivalent to interpreter)-native code-run

You can find that in the end, you need to become native code before it can be executed.

Three branches of JAVA:

1.J2SE--java standard edition standard version

2.J2ME--java Micro edition is generally located in embedded applications.

3.J2EE--java Enterprise Edition is generally the application of server-side programs.

Servlet is completely dependent on the server side

The essence of servlet is a helper.

Static website technology and dynamic website technology:

What is servlet Technology: CGI solution as the main Camp of Java

The role of the servlet container: the Servlet container, also known as the servlet engine, is part of a web server or application server that provides network services on top of sent requests and responses, decodes MIME-based requests, and formats MIME-based responses

With servlet, users access servlet by clicking on a link or entering URL directly into the browser's address

What the servlet container can provide:

1. Communication support: using the method provided by the container, you can easily let servlet talk to the web server without having to set up your own serversocket and listen on the port.

two。 Life cycle management

3. Multithreading support

4.JSP support

Tomcat is the Apache Software Foundation.

The core of Tomcat is divided into three parts:

1.web container-dealing with static pages

2.Catalina servlet-a servlet container-handles catalinaLay

3. And then there is the JSP container, which translates a JSP page into a servlet.

The difference between JSP and servlet: JSP writes Java code in HTML, and servlet writes HTML code in Java. In fact, JSP is servlet after passing through the container interpreter.

JSEE-- > sevlet--- > CGI

Sevlet program written by java

The Java container comes to call

JSP html-- > java tag-- > sevlet

The relationship between tomcat and servlet: tomcat is actually a program written by servlet in Java

As the name implies, JRE is the environment of Java runtime, including Java virtual machine and Java basic class library.

JDK, as its name implies, is a Java development kit, which is developed by programs writing Java programs in Java language, and is provided to programmers.

JDK:yum install jdk-8u144-linux

Java-version can be viewed

Tomcat installation method:

Download 1.lftp 172.17.0.1 > cd pub > cd sources > ls > cd 7.x86_64 > cd jdk > ls > get jdk-8u144-linux

Yum localinstall jdk.

Default path

Cd / usr/lib/jvm

Cd / usr/java/jdk1.8.0_144/bin

Cd.. Java]

two。 Set environment variabl

Vim / etc/profile.d/java.sh

Export JAVA_HOME=/usr/java/jdk1.8.0_144

Export JRE_HOME=$JAVA_HOME/jre

Export PATH=$JAVA_HOME/bin:$JRE_HOME/bin:$PATH

Chmod + x / etc/profile.d/java.sh

. / etc/profile.d/java.sh for reading

Echo $JAVA_HOME View Jdk

Java-version can check again whether the version has changed.

3.lftp 172.17.0.1 cd pub cd sources cd 7.x86_64 cd tomcat mget apache-tomcat-7.0.78.tar.gz solo-2.2.0.war (deployment file)

Tar-xvf apache.

Cd apache-tomcat-7.0.78

Ls View

Cd..

Mv apache-tomcat-7.0.78 / usr/local/tomcat

Cd / usr/local/tomcat

Ls

Cd bin

. / catalina.sh start runs tomcat

Netstat-tunlp

172.17. Vera 8080 access test

Cd / conf server.xml main configuration profile

1.server:server represents the entire Catalina servlet container. 2.service: service is an intermediate component that lives inside server: 3.Connector component: connector handles communication with client 4.Engine component: in tomcat Each service can contain only one servlet engine 5.Host component: a host or virtual host located inside the engine to receive requests and process them accordingly is similar to the Nginx server 6.Context component: a context represents a web application that runs in a specific virtual host A host can contain multiple context (representing web applications) information such as Nginx location web.xml web application description files context.xml can be used to configure databases logging.properties log system-related configuration

Tomcat page: manmger

Admin

Test the jsp script

Cd webapps

Mkdir test

Cd test

Vim index.jsp

Tomcat related configuration:

Cd / usr/local/tomcat

Cd conf

Vim tomcat-users.xml

< role rolename="manager-gui" < role rolename="admin-gui" < user username="tomcat" password="tomcat" roles="manager-gui,admin-gui"/>

. / bin/catalina.sh stop

. / bin/catalina.sh start

Deployment of Tomcat:

Deploy the solo package on ftp to Tomcat

Cp sols-2.2.0.war / usr/local/tomcat/webapps

Cd webapps

Mv solo-2.2.0.war / tmp

Cd webapps

Mv / tmp/solo-2.2.0.war. /

Cd logs log storage path

The principle of tomcat composition:

Service: the connector is combined with the engine

Connector: the connector is used to receive requests from users

Engine: the engine is used to process users' requests

Host: virtual host

Context: equivalent to location, that is, equivalent to routing, and can also be matched.

Servlet: it's the program.

The organizational structure of JSP webapp:

/: root directory of webapps

Index.jsp home page; cd / manager

Maven project management tool www.oschina.net java open source project

Mysql-uroot-p-D magedu < jeesns.sql Import File in magedu Database

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