ubuntu上postgresql导出数据库表

想把postgresql上某个数据库里所有的表导出
# sudo pg_dump -U postgres canvas_production > /opt/full.sql
结果：failed: FATAL:  Peer authentication failed for user "postgres"
解决：# sudo vi /etc/postgresql/9.1/main/pg_hba.conf
将
# Database administrative login by Unix domain socket
local   all             postgres                                peer
改为
# Database administrative login by Unix domain socket
local   all             postgres                                trust

保存后执行下面的命令重新加载配置文件:
sudo /etc/init.d/postgresql reload

# sudo pg_dump -U postgres canvas_production > /opt/full.sql

# file full.sql
full.sql: ASCII C program text, with very long lines
OK,成功了