MybatisPlus之QueryWrapper与LambdaQueryWrapper的用法及区别

/**
 * 1. QueryWrapper 用法示例
 */
List userList = userMapper.selectList(new QueryWrapper()
        .like("email", "24252")
        .between("age", 20, 22)
        .or()
        .eq("name", "zcx")
);
System.out.println("userList:" + userList.toString());

//2、排序用法
List users = userMapper.selectList(new QueryWrapper()
        .eq("nick_name", "xx")
        .orderByAsc("age")  //升序
        //                .orderByDesc("age") //降序
        .last("limit 0,3") //last用法：在sql末尾添加sql语句，有sql注入风险
);
System.out.println("users:"+users.toString());

/**
 * 2. LambdaQueryWrapper 用法示例
 */
LambdaQueryWrapper queryWrapper = new LambdaQueryWrapper<>();
queryWrapper.eq(UserDo::getAccount, account);
queryWrapper.eq(UserDo::getIsDelete, 0);
queryWrapper.like(UserDo::getName,"lk");
queryWrapper.between(UserDo::getAge,18,20);
// queryWrapper.orderByAsc(UserDo::getDeptNo);
UserDo user = userMapper.selectOne(queryWrapper);
Integer count = userMapper.selectCount(queryWrapper);

UserDo user1 = userMapper.selectOne(new LambdaQueryWrapper()
.eq(UserDo::getAccount, username));

/**
 * 3. 区别
 * 
 * QueryWrapper 的列名匹配使用的是 “数据库中的字段名(一般是下划线规则)”
 * LambdaQueryWrapper 的列名匹配使用的是“Lambda的语法，偏向于对象”
 * 不同写“列名”，而是使用纯java的方式，避免了拼写错误(LambdaQueryWrapper 的写法如果有错，
 * 则在编译期就会报错，而QueryWrapper需要运行的时候调用该方法才会报错)
 * 所以LambdaQueryWrapper 更优于 QueryWrapper
 */