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Database: add, delete, modify and query commands for databases and tables Connect to mysql To connect to the MySQL server: mysql -u root -p (Note: my user name is root), and then enter the password to connect again show database show databases; Create a database and set the encoding format to utf8 create database if not exists Library nam ...

13.MyBatis caching mechanism 1. Why cache? When users frequently query some fixed data, they query these data from the database for the first time and save them in the cache. When users query these data again, they do not need to query through the database, but query in the cache. Reduce the loss caused by network connection and database quer ...

preface What is binlog There are various types of logs in mysql, which record mysql, including startup, operation, connection, change and other operations, and binlog is the most important log. It records the changes of all MySQL data and stores it on disk in binary form binlg records all table structure changes (CREATE, ALTER TABLE... ...

Official Chinese documents Zabbix user manual catalogue Solve the problem of no network after centos7 installationInstall MySQLInstalling zabbixp3 common monitoring commandsCustom monitorCustom triggerMail alarmModify email contentVx alarmSecondary development Customize menu Modify footer Replace logoMonitor network trafficMonitoring diskMo ...

1, ForewordStorage engine is a special name for MySQL. Oracle, the big brother in the database industry, SQL Server, PostgreSQL and so on do not have a storage engine.An important feature that distinguishes MySQL from other databases is its pluggable table storage engine.Engine is a foreign transliterated word, which is traditionally regarded a ...

1, Index principleIndex is an important method to improve the performance of database query.Use indexes to quickly find rows in a column that contain specific values. If you do not use an index, you must start reading from the first record. You may have to read the whole table to find the relevant rows.Using an index is like looking up a dictio ...

1, Character set overviewCharacter Set is a collection of multiple characters. There are many kinds of character sets. Each Character Set contains different numbers of characters. Common Character Set names: ASCII, GB2312, BIG5, Unicode, etc.UTF (Unicode transformation format) is one of the ways to use Unicode, that is, to convert Unicode to a ...

Author: Yang TaotaoSenior database expert, specializing in MySQL for more than ten years. He is good at backup and recovery, SQL tuning, monitoring, operation and maintenance, high availability architecture design related to MySQL, PostgreSQL, MongoDB and other open source databases. At present, he works in aikesheng, providing MySQL related te ...

Ioc and annotation development 1. Spring configuration data source 1.1 function of data source (connection pool) Data source (connection pool) is the key to improve program performanceInstantiate the data source in advance and initialize some connection resourcesGet from data source when using connection resourcesReturn the connected res ...

/******************* postgresql database test starts***********************/   --This test is based on pg database version 10.11 postgres=# select version();                            version -------------------------------------------------------------  PostgreSQL 10.11, compiled by Visual C++ build 1800, 64-bit (1 Row record) --Create a ...