1.根据id查询
User user = userMapper.selectById(id);
2.多个id
User user = userMapper.selectBatchIds(id1,id2,id3);
3.多条件查询
Map map = new HashMap();
map.put(name,"AA");
map.put(age,);
User user = userMapper.selectByMap(map);
4.分页查询
5.逻辑删除
6.条件查询
