ideras

Thoughts, stories and ideas.

database principle and application

Multi-table query operation of the database-query students who have only taken 1 course, and display student ID, name, and course name.

Article DirectoryPrefaceOne, create a database and tablesTwo, database display2. Query students who have only taken 1 course, and display student ID, name, and course name.to sum upPrefaceIn my opinion, the database is really a magical thing. Not only is it very profound, but it also puts a certain pressure

java

Redis (1)-concept and foundation

Article Directorymain contentIntroduceSolve CPU and memory pressureSolve IO pressureNoSQL databaseOverviewFeaturesApplicable sceneexampleMemcacheRedisMongoDBRedis overviewWhat is RedisFeaturesscenes to be usedHot data cacheUse of time-limited businessCounter related issuesDistributed lockDelay operationQuestions about leaderboardsStorage of mutual relations such as likes, friends, etc.Simple queueRedis technologyFive commonly used data typesStringList listSet collectionHashZset(sorted set) ordered setSkip listDetailed

ssm

AOP aspect-oriented programming

Article DirectoryAOP aspect-oriented programmingScene simulationImproveRealize with dynamic proxySpring implements the AOP function, and the bottom layer is a dynamic proxyProper nounsAOP implementationJoinPoint obtains the information and return value of the target parameterAOP aspect-oriented programmingAOP (Aspect Oriented Programming): Aspect Oriented Programming OOP (Object Oriented Programming): object-oriented programming Aspect-oriented programming: Based on

zabbix monitoring

Operation and maintenance actual combat Zabbix monitoring advanced

Operation and maintenance actual combat Zabbix monitoring advancedPercona Monitoring PluginsZabbix monitor TomcatAdd support for JMX interfacePercona Monitoring PluginsPercona Monitoring PluginsWith 190多个monitoring items. It is obviously unrealistic to add so many monitoring items manually, you need to use a template to import ##查看其附带的两个目录中的内容 cd /var/lib/zabbix/percona/scripts/ ##包含搜集数据所需的shell脚本和php文件 get_

operation and maintenance

Operation and maintenance of the business connection between Redis and Mysql

Operation and maintenance of the business connection between Redis and MysqlRedis and MqSQL business connectionRealize automatic synchronizationPart of the operation processRedis and MqSQL business connectionNeed to prepare 3a server Server1Turn onredisServer2For installation phpand nginxsimulation of data for synchronization informationClientServer3Install mariadbasmysqlThe business logic is like this, the written mysqldata is Server2synchronized

caché global

Chapter 2 Global Variable Structure (2)

Article DirectoryChapter 2 Global Variable Structure (2)Physical structure of global variablesReference global variablesSet global variable mappingUse different scopes of global and subscriptsRecord changesExtended global variable referenceSquare bracket syntaxEnvironmental grammarChapter 2 Global Variable Structure (2)Physical structure of global variablesGlobal variables are stored in physical files using a highly optimized