SpringBoot内置数据源的持久化与解决方案

       <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>druid-spring-boot-starter</artifactId>
            <version>1.2.8</version>
        </dependency>

        <dependency>
            <groupId>com.baomidou</groupId>
            <artifactId>mybatis-plus-boot-starter</artifactId>
            <version>3.5.1</version>
        </dependency>        

        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
        </dependency>
        <dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-jdbc</artifactId>
        </dependency>
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
        </dependency>

package com.jkj;
import com.jkj.dao.BookDao;
import com.jkj.domian.Book;
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.jdbc.core.RowMapper;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.List;
@SpringBootTest
class Springboot09SqlApplicationTests {
	/*@Autowired
	private BookDao bookDao;*/
	/*@Test
	void contextLoads() {
		*//*bookDao.selectById(2);*//*
	}*/
	@Autowired
	private JdbcTemplate jdbcTemplate;
	@Test
	void JDBCTEST() {
//        jdbcTemplate.update();//增删改
//        jdbcTemplate.query(); //查询
//        jdbcTemplate.queryForObject();//查询单个对象
/*     一般不使用这种格式
        String sql ="select * from tbl_book";
        List<Map<String,Object>> maps = jdbcTemplate.queryForList(sql);
        System.out.println(maps);*/
		RowMapper<Book> rm = new RowMapper<Book>() {
			@Override
			public Book mapRow(ResultSet resultSet, int i) throws SQLException {
//              ResultSet resultSet 其实就是结果集
				Book temp = new Book();
				temp.setId(resultSet.getInt("id"));
				temp.setName(resultSet.getString("name"));
				temp.setType(resultSet.getString("type"));
				temp.setDescription(resultSet.getString("description"));
				return temp;
			}
		};
		String sql = "select * from tbl_book  ";
		List<Book> list = jdbcTemplate.query(sql, rm);
		System.out.println(list);
	}
}

       <dependency>
			<groupId>com.h2database</groupId>
			<artifactId>h2</artifactId>
		</dependency>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-data-jpa</artifactId>
		</dependency>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-web</artifactId>
		</dependency>

@Test
	void testJdbcTemplateSave(@Autowired JdbcTemplate jdbcTemplate){
		String sql="insert into tbl_book values(3,'斗罗大陆','科幻','左手蓝银草右手昊天锤')";
		jdbcTemplate.update(sql);
	}