Juicio del valor nulo de PostgreSQL

Juicio de valor nulo

-- 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;

sentencia no nula

-- 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;

Resumir