@TestpublicvoidqueryWrapperOne() { QueryWrapper<User> queryWrapper =new QueryWrapper<>(); queryWrapper. isNull("name") .ge("age",23) .isNotNull("email");// 逻辑删除int result = userMapper.delete(queryWrapper); System.out.println(result);// 最终的语句为:UPDATE user SET deleted=1 WHERE de...
publicvoidqueryWrapperThree() { QueryWrapper<User>queryWrapper=newQueryWrapper<>(); queryWrapper.between("age",20,30); Integercount=userMapper.selectCount(queryWrapper); System.out.println(count); } 1. 2. 3. 4. 5. 6. 7. 8. allEq allEq 全部 eq(或个别 isNull) 个别参数说明: params...
QueryWrapper<User>queryWrapper = newQueryWrapper<>(); queryWrapper.eq("name","Tom"); Useruser = userMapper.selectOne(queryWrapper);//只能返回一条记录,多余一条则抛出异常System.out.println(user); } 3 between、notBetween 包含大小边界 @TestpublicvoidtestSelectCount(){ QueryWrapper<User>queryWrapper =...
QueryWrapper<User> queryWrapper = new QueryWrapper<>(); queryWrapper.eq("name", "lqf"); Integer count = mapper.selectCount(queryWrapper); System.out.println(count); } /** * * 根据 entity 条件,查询全部记录 * * * @param queryWrapper 实体对象封装操作类(可以为 null)为null查询全部 */ @...
System.out.println("delete return count = " + result); } 二、eq、ne @Test public void testSelectOne() { QueryWrapper&lqdgpact;User> queryWrapper = new QueryWrapper<>(); queryWrapper.eq("name", "Tom"); Useruser = userMapper.selectOne(queryWrapper);//只能返回一条记录,多余一条则抛出异常 ...
voidupdateBalanceByIds(@Param("ew")LambdaQueryWrapper<User>wrapper,@Param("amount")intamount); 3.在xml中自定义sql,并使用Wrapper条件 例子: Service接口 提供了一个iService接口,提供了大量用于增删改查的方法 增 删 改 查 查单个,查数目(count) ...
.isNotNull("email"); int delete = mapper.delete(queryWrapper); System.out.println("delete return count = " + delete); } /** ** 根据 entity 条件,查询一条记录, * 这里和上方删除构造条件一样,只是seletOne返回的是一条实体记录,当出现多条时会报错 ...
private Map<String, Double> queryWeight() { QueryWrapper<TagWeight> wrapper = new QueryWrappe...
queryWrapper.like("s_name", "李"); List<Student> students = studentMapper.selectList(queryWrapper); System.out.println("students = " + students); } @Test public void query04(){ // 统计 selectCount // QueryWrapper<Student> queryWrapper = new QueryWrapper<>(); ...
补充:Mybatis-Plus QueryWrapper +sql自定义查询 一: 需要自定义的QueryWrapper查询工具类,定义查询规则 publicstaticfinalString SQL_RULES_COLUMN="SQL_RULES_COLUMN";privatestaticfinalString BEGIN="_begin";// 字段范围查询开始标识privatestaticfinalString END="_end";// 字段范围查询结束标识privatestaticfinalStri...