无论多数据源,还是单数据源,分页都一样,刚开始出了点错,是因为PageHelper的版本问题

这里用的SpringBoot3    SpringBoot2应该是没有问题的

相关代码

dynamic-datasource+Mybatis多数据源使用-CSDN博客

依赖

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>3.2.8</version>
        <relativePath/> <!-- lookup parent from repository -->
    </parent>
    <groupId>com.example</groupId>
    <artifactId>dynamic-datasource</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>dynamic-datasource</name>
    <description>Demo project for Spring Boot</description>
    <url/>
    <licenses>
        <license/>
    </licenses>
    <developers>
        <developer/>
    </developers>
    <scm>
        <connection/>
        <developerConnection/>
        <tag/>
        <url/>
    </scm>
    <properties>
        <java.version>17</java.version>
    </properties>
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <dependency>
            <groupId>org.mybatis.spring.boot</groupId>
            <artifactId>mybatis-spring-boot-starter</artifactId>
            <version>3.0.3</version>
        </dependency>

        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>8.0.33</version>
        </dependency>
        <!--dynamic-datasource -->
        <dependency>
            <groupId>com.baomidou</groupId>
            <artifactId>dynamic-datasource-spring-boot3-starter</artifactId>
            <version>4.3.1</version>
        </dependency>
        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid-spring-boot-starter</artifactId>
            <version>1.2.21</version>
        </dependency>
        <!--分页 低版本要自己额外配置下 -->
<!--        <dependency>-->
<!--            <groupId>com.github.pagehelper</groupId>-->
<!--            <artifactId>pagehelper-spring-boot-starter</artifactId>-->
<!--            <version>1.3.1</version>-->
<!--        </dependency>-->
        <dependency>
            <groupId>com.github.pagehelper</groupId>
            <artifactId>pagehelper-spring-boot-starter</artifactId>
            <version>2.1.0</version>
        </dependency>

        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
                <configuration>
                    <excludes>
                        <exclude>
                            <groupId>org.projectlombok</groupId>
                            <artifactId>lombok</artifactId>
                        </exclude>
                    </excludes>
                </configuration>
            </plugin>
        </plugins>
    </build>

</project>

PageHelper配置

#PageHelper 配置
#推荐明确指定数据库方言
pagehelper.helperDialect=mysql
#合理化分页参数，避免异常页码导致的错误  启用后，当 pageNum 小于等于 0 时，会自动查询第一页的数据；当 pageNum 大于总页数时，会自动查询最后一页的数据。
pagehelper.reasonable=true
#支持通过方法参数传递分页参数  PageHelper.startPage(1,2)
pagehelper.supportMethodsArguments=true
#自动生成 count 查询语句用于计算总记录数（默认配置）
pagehelper.params=count=countSql
#在运行时自动识别和设置数据库方言
#pagehelper.autoRuntimeDialect=true

持久层   PageHelper会拦截sql  拼接 select * from xxx limit (pageNum-1)*pageSize,pageSize

如果非要在SpringBoot3使用低版本PageHelper

package com.example.dynamicdatasource.config;

import com.github.pagehelper.PageInterceptor;
import org.apache.ibatis.session.SqlSessionFactory;
import org.mybatis.spring.SqlSessionFactoryBean;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

import javax.sql.DataSource;
import java.util.Properties;

/**
 * @author hrui
 * @date 2024/8/6 21:03
 */
@Configuration
public class MyBatisConfig {
    /*因使用的SpringBoot3  低版本PageHelp要额外配置   application.properties中的pageHelp无法set到参数  高版本没有问题 不需要设置*/
//    @Bean
//    public SqlSessionFactory sqlSessionFactory(DataSource dataSource) throws Exception {
//        org.apache.ibatis.session.Configuration configuration = new org.apache.ibatis.session.Configuration();
//        SqlSessionFactoryBean factoryBean = new SqlSessionFactoryBean();
//        factoryBean.setDataSource(dataSource);
//
//        // 添加PageHelper分页插件
//        PageInterceptor pageInterceptor = new PageInterceptor();
//        Properties properties = new Properties();
//        properties.setProperty("helperDialect", "mysql");
//        properties.setProperty("reasonable", "true");
//        properties.setProperty("supportMethodsArguments", "true");
//        properties.setProperty("params", "count=countSql");
//        pageInterceptor.setProperties(properties);
//
//        configuration.addInterceptor(pageInterceptor);
//        factoryBean.setConfiguration(configuration);
//        return factoryBean.getObject();
//    }
}