1. 數據源配置代碼：

import com.alibaba.druid.pool.DruidDataSource;
import lombok.extern.slf4j.Slf4j;
import org.springframework.boot.autoconfigure.condition.ConditionalOnProperty;
import org.springframework.boot.autoconfigure.jdbc.DataSourceBuilder;
import org.springframework.boot.context.properties.ConfigurationProperties;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.jdbc.core.JdbcTemplate;import javax.annotation.PostConstruct;
import java.sql.Connection;
import java.sql.DatabaseMetaData;
import java.sql.SQLException;@Slf4j
@Configuration
@ConditionalOnProperty(prefix = "sms.secondary", name = "enabled", havingValue = "true", matchIfMissing = false) //配置是否啟用
public class DsDbConfiguration {@Bean@ConfigurationProperties("spring.datasource.secondary.ds")public DruidDataSource jjxxDataSource() {DruidDataSource dataSource = (DruidDataSource) DataSourceBuilder.create().type(DruidDataSource.class).build();return dataSource;}@Beanpublic JdbcTemplate jjxxDataTemplate() {return new JdbcTemplate(jjxxDataSource());}@PostConstructpublic void testConnection() {try (Connection conn = jjxxDataSource().getConnection()) {DatabaseMetaData meta = conn.getMetaData();log.info("MySQL 第二數據源 連接成功! 服務版本: {}", meta.getDatabaseProductVersion());} catch (SQLException e) {log.error("MySQL  第二數據源 連接失敗", e);log.error(e.getMessage(), e);}}
}

2.新建entity

import lombok.Data;import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.Id;
import java.util.Date;/***  Entity* @author * @time   */
@Data
@Entity
public class ThirdEntity{private static final long serialVersionUID = 1L;/*** 發案時間*/@Column(name = "fasj")private Date fasj;/*** 發案行政區劃*/@Column(name = "faxzqh")private String faxzqh;/***報警電話*/@Column(name = "bjdh")private String bjdh;//省略其他字段}

3. 查詢數據：

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.jdbc.core.BeanPropertyRowMapper;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.jdbc.core.namedparam.MapSqlParameterSource;
import org.springframework.jdbc.core.namedparam.NamedParameterJdbcTemplate;
import org.springframework.stereotype.Repository;import java.util.List;@Repository
public class JieJingDao {private final NamedParameterJdbcTemplate namedParameterJdbcTemplate;@Autowiredpublic JieJingDao(@Qualifier("jjxxDataTemplate") JdbcTemplate jdbcTemplate) {this.namedParameterJdbcTemplate = new NamedParameterJdbcTemplate(jdbcTemplate);}// 查詢多個記錄public List<ThirdEntity> queryEntityList(String start, String end) {String sql = "SELECT * FROM third_table WHERE  DATE_FORMAT(bjsj,'%Y-%m-%d %H:%i:%S') >=:start and DATE_FORMAT(bjsj,'%Y-%m-%d %H:%i:%S') <= :end";MapSqlParameterSource params = new MapSqlParameterSource();params.addValue("start", start);params.addValue("end", end);return namedParameterJdbcTemplate.query(sql, params, new BeanPropertyRowMapper<>(ThirdEntity.class));}}

4. 數據源配置信息：

spring.datasource.secondary.ds.url: jdbc:mysql://localhost:3306/thirdDatabase?useUnicode=true&characterEncoding=utf-8&serverTimezone=UTC&useSSL=false&rewriteBatchedStatements=true
spring.datasource.secondary.ds.url.username: root
spring.datasource.secondary.ds.url.password: root