3. mybatis # 与 $ 的区别

mybatis # 与 $ 的区别

1.# % 号必须写在test中

应用场景：模糊查询

配置文档mapper.xml

<select id="selectBlogByTitle" parameterType="string" resultMap="blogResultMap">

select * from blog where title like #{tilte}

</select>

 

接口 mapper

List<Blog> selectBlogByTitle(String title);

 

测试Test

@Test

public void testSelectBlogByTitle(){

 

SqlSession session = MybatisUtil.getSqlSession();

BlogMapper blogMapper = session.getMapper(BlogMapper.class);

List<Blog> blogList = blogMapper.selectBlogByTitle("%w%");

session.close();

System.out.println("<<<<<------------>>>>>:"+blogList);

 

}

2.$ 如果是单值的话只能用value ，并且用单引号，可以写在xml中

配置文档mapper.xml

<select id="selectBlogByTitle2" parameterType="string" resultMap="blogResultMap">

select * from blog where title like '${value}'

</select>

%号还可以写在xml中

<select id="selectBlogByTitle2" parameterType="string" resultMap="blogResultMap">

select * from blog where title like '%${value}%'

</select>

 

接口 mapper

List<Blog> selectBlogByTitle2(String title);

测试Test

@Test

public void testSelectBlogByTitle2(){

 

SqlSession session = MybatisUtil.getSqlSession();

BlogMapper blogMapper = session.getMapper(BlogMapper.class);

List<Blog> blogList = blogMapper.selectBlogByTitle2("%w%");

session.close();

System.out.println("<<<<<------------>>>>>:"+blogList);

 

}

不写% 号在测试中

@Test

public void testSelectBlogByTitle2(){

 

SqlSession session = MybatisUtil.getSqlSession();

BlogMapper blogMapper = session.getMapper(BlogMapper.class);

List<Blog> blogList = blogMapper.selectBlogByTitle2("w");

session.close();

System.out.println("<<<<<------------>>>>>:"+blogList);

 

}

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