Postgres数据库用户密码有效期设置

pg_user或pg_shadow中：
     列valuntil值为infinity或空值表示用户密码永不过期；默认为空
 
修改用户密码过期时间:
alter user user_name with valid until '2018-01-01 08:00:00';

修改用户密码永不过期:
alter user user_name with valid until 'infinity';

highgo=# select * from pg_user;

 usename | usesysid | usecreatedb | usesuper | usecatupd | userepl |  passwd  | valuntil | useconfig 
---------+----------+-------------+----------+-----------+---------+----------+----------+-----------
 highgo  |       10 | t           | t        | t         | t       | ******** |          | 
 a       |    49231 |