Mybatis 的动态SQL，批量增删查改

个人博客网：https://wushaopei.github.io/    (你想要这里多有)

批量增删改的接口：

public interface BookService {

        //批量增加	

	int saveList(List<Book> records);
	//批量查找

	List<Book> selectList(List<Integer> ids);

        //批量删除
	int deleteList(List<Integer> ids);

        //批量修改
	int updateList(List<Book> bookList);

}

接口实现类：

@Service
public class BookServiceImpl implements BookService{

	@Autowired
	BookMapper bookMapper;

	@Override
	public int saveList(List<Book> list) {
		// TODO Auto-generated method stub
		int count = bookMapper.inserts(list);
		return count;
	}

	@Override
	public List<Book> selectList(List<Integer> ids) {
		// TODO Auto-generated method stub

		List<Book> books = bookMapper.selectByIds(ids);
		return books;
	}

	@Override
	public int deleteList(List<Integer> ids) {
		// TODO Auto-generated method stub
		return bookMapper.deleteByPrimaryKeys(ids);
	}

	@Override
	public int updateList(List<Book> bookList) {
		// TODO Auto-generated method stub

		return bookMapper.updateByPrimaryKeys(bookList);
	}

}

对应的实体类 JavaBean ：

public class Book {
    public Book(Integer id, String name, String author, BigDecimal price, Integer sales, Integer stock) {
		super();
		this.id = id;
		this.name = name;
		this.author = author;
		this.price = price;
		this.sales = sales;
		this.stock = stock;
	}
............省略

mapper.xml 中SQL 语句的编写：

  <!-- 批量根据id进行删除 -->
  <delete id="deleteByPrimaryKeys" parameterType="java.util.List"  >
    delete from t_book
    where id in
	<foreach collection="list" item="id" open="(" close=")" separator="," >
	      #{id,jdbcType=INTEGER}
	</foreach>
  </delete>

    <!-- 批量进行插入数据 -->

	<insert id="inserts" parameterType="java.util.List">

		insert into t_book (id,name,author,price,sales,stock) values

		<foreach collection="list" item="Book" separator="," index="index">

		(null, #{Book.name}, #{Book.author}, #{Book.price}, #{Book.sales}, #{Book.stock})

		</foreach>

	</insert>

  <!-- 批量根据id进行修改 -->

   <update id="updateByPrimaryKeys" parameterType="java.util.List" >
	    update t_book
	    	<trim prefix="set" suffixOverrides=",">
	    	 <trim prefix="name=case" suffix="end,">
	    	 	<foreach collection="list" item="Book" index="index">
	    			<if test="Book.name!=null">
	    				when id=#{Book.id} then #{Book.name}
	    			</if>
	    		</foreach>
	    	 </trim>
	    	 <trim prefix="name=case" suffix="end,">
	    	 	<foreach collection="list" item="Book"  index="index">
	    			<if test="Book.author!=null">
	    				when id=#{Book.id} then #{Book.author}
	    			</if>
	    		</foreach>
	    	 </trim>
	    	 <trim prefix="name=case" suffix="end,">
	    	 	<foreach collection="list" item="Book"  index="index">
	    			<if test="Book.price!=null">
	    				when id=#{Book.id} then #{Book.price}
	    			</if>
	    		</foreach>
	    	 </trim>
	    	 <trim prefix="name=case" suffix="end,">
	    	 	<foreach collection="list" item="Book"  index="index">
	    			<if test="Book.sales!=null">
	    				when id=#{Book.id} then #{Book.sales}
	    			</if>
	    		</foreach>
	    	 </trim>
	    	 <trim prefix="name=case" suffix="end,">
	    	 	<foreach collection="list" item="Book"  index="index">
	    			<if test="Book.stock!=null">
	    				when id=#{Book.id} then #{Book.stock}
	    			</if>
	    		</foreach>
	    	 </trim>
	    	</trim>
	    	where
	    	 <foreach  collection="list" separator="or" item="Book" index="index">
	    		id=#{Book.id,jdbcType=INTEGER}
	    	</foreach>
  </update>

  <!-- 批量根据id查找 -->

  <select id="selectByIds" resultMap="BaseResultMap" parameterType="java.lang.Integer" >
    select id, name, author, price, sales, stock
    from t_book
    where id in
    <foreach collection="list" item="id" open="(" close=")" separator="," >
      #{id,jdbcType=INTEGER}
    </foreach> 

  </select>
 

测试： test 对批量操作进行测试是否成功：

/*
	 *  批量插入
	 * */
	@Test
	public void InsertBookServices()throws SQLException {

		List<Book> bookList = new ArrayList<>();
		bookList.add(new Book(null,"生活1","奕1君",new BigDecimal(1),1,1));
		bookList.add(new Book(null,"生活2","奕2君",new BigDecimal(2),2,2));
		bookList.add(new Book(null,"生活3","奕3君",new BigDecimal(3),3,3));
		bookList.add(new Book(null,"生活4","奕4君",new BigDecimal(4),4,4));
		bookList.add(new Book(null,"生活5","奕5君",new BigDecimal(5),5,5));

		int count = bookService.saveList(bookList);
		System.out.println(count);
	}

	/*
	 *  批量查询
	 * */
	@Test
	public void SelectBookService()throws SQLException {

		List<Integer> Ids = new ArrayList();
		Ids.add(1);
		Ids.add(2);
		Ids.add(3);
		Ids.add(4);

		List<Book> Books = bookService.selectList(Ids);

		for(Book book : Books) {
			System.out.println(book.toString());
		}
	}

	/*
	 *  批量删除
	 * */
	@Test
	public void DeleteBookService()throws SQLException {

		List<Integer> Ids = new ArrayList();
		Ids.add(1);
		Ids.add(2);
		Ids.add(3);
		Ids.add(4);

		int  counts = bookService.deleteList(Ids);
		System.out.println(counts);

	}

	/*
	 *  批量更新
	 * */
	@Test
	public void UpdateBookService()throws SQLException {

		List<Book> bookList = new ArrayList<>();
		bookList.add(new Book(6,"生活6","奕6君",new BigDecimal(1),1,1));
//		bookList.add(new Book(7,"生活7","奕7君",new BigDecimal(2),2,2));
		bookList.add(new Book(8,"生活8","奕8君",new BigDecimal(3),3,3));
		bookList.add(new Book(9,"生活9","奕9君",new BigDecimal(4),4,4));
		bookList.add(new Book(10,"生活10","奕10君",new BigDecimal(5),5,5));

		int count = bookService.updateList(bookList);
		System.out.println(count);

	}

链接：https://pan.baidu.com/s/1oAYg5X8eeqf18dUTU1bUpA
提取码：jznv
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