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1. Overview of distributed global id and problems caused When creating a table, we use self increment for the primary key id to uniquely distinguish the dataIn the scenario of sub database and sub table, the problem of self adding id cannot be solvedDuplicate IDs of two different business data will lead to query errors or related data pr ...

Mybatis task 1: basic application Main contents of course tasks: Framework introductionMybatis: ORMquick get startBrief overview of mapping filesImplement CRUDIntroduction to core configuration fileapi introductionDevelopment and use of dao layer of mybatis (interface proxy mode) SSM = springmvc + spring + mybatis I. Introduction to the fra ...

File network disk resources required for problem solving: Link: https://pan.baidu.com/s/1uMrhVmHlvEQ-sEGZtqhqiw Extraction code: kkab File list: libnsl-2.17.so libcrypto.so.1.0.2k libssl.so.1.0.2k libreadline.so.6.2 1. Environmental description    firewall: after it is turned on, various settings are required, which may cause ...

Hikari+jdbcTemplate+mysql pom.xml <!-- Connection pool, jdbc，Transaction related--> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-data-jdbc</artifactId> </dependency> <!-- mysql drive--> ...

Connect to the database through the XML configuration file and configure the path of the XML file that executes the SQL statement <?xml version="1.0" encoding="UTF-8" ?> <!DOCTYPE configuration PUBLIC "-//mybatis.org//DTD Config 3.0//EN" "http://mybatis.org/dtd/mybatis-3-config.dtd"> <configuration> <environments defaul ...

JDBC Concept: Java DataBase Connectivity - Java database connection, Java language operation databaseJDBC essence: in fact, it is an officially defined set of rules for operating all relational databases, that is, interfaces. Each database manufacturer implements this interface and provides database driver jar package. We can use this set of i ...

1. Configure YUM source 1.1 download mysql source installation package [root@chris /]# wget http://dev.mysql.com/get/mysql57-community-release-el7-11.noarch.rpm 1.2 installing mysql source [root@chris /]# yum localinstall mysql57-community-release-el7-11.noarch.rpm 1.3 check whether the mysql source is successfully installed [root@chris ...

InnoDB logical storage unit is mainly divided into table space, segment, area and page 1. Tablespace All data of InnoDB is stored in table space, which is divided into system table space and independent table space MySQL5. After 7, there are temporary table spaces and general table spaces 1) SYSTEM tablespace The system table space is main ...

The bytea binary type in openGauss/MogDB database is limited by the segment size compilation parameter and cannot exceed 1GB by default. If the data stored in the field exceeds 1GB, the lo (Large Object) extension type can be used.01lo type needs to create lo extension first$ gsql -p5432 -Uomm postgres -r gsql ((MogDB 2.0.1 build f892ccb7) comp ...

First, insert multiple pieces of data. Options: foreach loop insertSplicing sql, one executionInsert using batch function 1. foreach insertion First obtain the list, and then perform a database operation for each piece of data to insert data: @SpringBootTest @MapperScan("com.aphysia.springdemo.mapper") class SpringdemoApplicationTests { ...