debian上安装postgresql的dblink postgresql9.1从debian官网上下载安装的包里面没有dblink,以安装postgresql9.0为主。 安装dblink前首先检 查系统是否装载软件postgresql-contrib-9.0,如果没有装此软件到debian的官方网站上下载安装安装命令: ~# apt-get i
debian上安装postgresql的dblink
postgresql9.1从debian官网上下载安装的包里面没有dblink,以安装postgresql9.0为主。
安装dblink前首先检 查系统是否装载软件postgresql-contrib-9.0,如果没有装此软件到debian的官方网站上下载安装安装命令:
~# apt-get install postgresql-contrib-9.0
安装软件后,查询dblink.sql的路径。命令:
~# dpkg -S dblink.sql
查询后结果:
postgresql-contrib-9.0: /usr/share/postgresql/9.0/contrib/dblink.sql
接着切换用户。命令
~# su - postgres
www.2cto.com
接口执行安装dblink。命令
~# psql -p 5432 -h 192.168.1.x dbname
安装成功后进入数据库
~# psql -p 5432 -h 192.168.1.x -U dbname
然后建立dblink
select dblink_connect('host=192.168.1.y port=5432 user=xxx dbname=xxx password=xxx');
如果建立连接的时候提示让你检查权限,你要去文件中把你的配置trust改成md5。
访问数据库表
select id from dblink('select a from t1 where a=''a'' ') as t1(id vachar(100));
关闭dblink
select dblink_disconnect();
第一次查询的时候可能要建立管道查询数据会比较慢,但是第二次以后就会很快了。

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