如何备份和恢复一个PostgreSQL数据库？

Question

大师我需要备份和恢复一个PostgreSQL数据库。 我的os版本是Ubuntu-14.04 64bit，PostgreSQL是：

gid: ~/works $ pg_config --version
PostgreSQL 9.3.15

我使用pg_dump来备份数据库：

gid: ~/works $ pg_dump -U db_name_user -F t db_name > db_name.tar

我尝试使用pg_restore来恢复数据库并失败：

gid: ~/works $ pg_restore -U db_name_user -F t -d db_name db_name.tar

pg_restore: [archiver (db)] Error while PROCESSING TOC:
pg_restore: [archiver (db)] Error from TOC entry 3621; 0 0 COMMENT EXTENSION plpgsql 
pg_restore: [archiver (db)] could not execute query: ERROR:  must be owner of extension plpgsql
Command was: COMMENT ON EXTENSION plpgsql IS 'PL/pgSQL procedural language';

pg_restore: WARNING:  no privileges could be revoked for "public"
pg_restore: WARNING:  no privileges could be revoked for "public"
pg_restore: WARNING:  no privileges were granted for "public"
pg_restore: WARNING:  no privileges were granted for "public"
WARNING: errors ignored on restore: 1

我不知道这意味着什么？ 我如何备份和恢复PostgreSQL数据库？

非常感谢。

------------------------ update 1 ------------------------

即使我在pg_dump和pg_restore中添加了“--no-owner”选项，我仍然会收到相同的错误消息：

gid:~/works $ pg_restore -U db_name_user -O -Ft -d db_name db_name.tar 
pg_restore: [archiver (db)] Error while PROCESSING TOC:
pg_restore: [archiver (db)] Error from TOC entry 3621; 0 0 COMMENT EXTENSION plpgsql 
pg_restore: [archiver (db)] could not execute query: ERROR:  must be owner of extension plpgsql
    Command was: COMMENT ON EXTENSION plpgsql IS 'PL/pgSQL procedural language';  

pg_restore: WARNING:  no privileges could be revoked for "public"
pg_restore: WARNING:  no privileges could be revoked for "public"
pg_restore: WARNING:  no privileges were granted for "public"
pg_restore: WARNING:  no privileges were granted for "public"
WARNING: errors ignored on restore: 1

Answer 1

您可以忽略评论语言时的错误 - 它不会影响您的代码。 还要考虑不使用所有者来避免此类警告。 但请记住，所有者将是您在pg_restore上连接的用户，而不是原始用户。 请阅读文档： https ： //www.postgresql.org/docs/current/static/app-pgrestore.html ：

-O

--no-owner不输出命令来设置对象的所有权以匹配原始数据库。 默认情况下，pg_restore发出ALTER OWNER或SET SESSION AUTHORIZATION语句以设置创建的模式元素的所有权。 除非与超级用户（或拥有脚本中所有对象的同一用户）建立与数据库的初始连接，否则这些语句将失败。 使用-O，任何用户名都可以用于初始连接，并且该用户将拥有所有创建的对象。