PostgreSQL空值的判断
- 空值判断
- 非空判断
- 总结
空值判断
-- 查询为空的 is null,sql简写isnull
select * from employees where manager_id isnull;
select * from employees where manager_id is null;
非空判断
-- 查询不为空的 is not null;sql简写notnull
select * from employees where manager_id is not null;
select * from employees where manager_id notnull;
总结
![pytorch_lightning报错 You requested gpu: [1]，But your machine only has: [0]](https://img-blog.csdnimg.cn/6288ae88d7ca4f909f35ce3d2ba8f771.png)
