PostgreSQL快速入门
PostgreSQL快速入门 在Ubuntu系统中怎样安装和配置PostgreSQL服务器 介绍 PostgreSQL是一个强大的关系型数据库管理系统,它按照BSD许可[1]发行。PostgreSQL包含很多高级的特性,拥有良好的性能和很好的适用性。 PostgreSQL绑定了很多种编程语言,例如 C, C++
PostgreSQL快速入门
在Ubuntu系统中怎样安装和配置PostgreSQL服务器
介绍
PostgreSQL是一个强大的关系型数据库管理系统,它按照BSD许可[1]发行。PostgreSQL包含很多高级的特性,拥有良好的性能和很好的适用性。
PostgreSQL绑定了很多种编程语言,例如 C, C++, Python, Java, PHP, Ruby等 ,它可以操作很多东西,从简单的Web应用程序到拥有数百万条记录的庞大数据库。
安装
你可以使用命令行安装PostgreSQL,输入:
sudo apt-get install postgresql
pgAdmin III 是一个方便的PostgreSQL图形客户端,它很适合初学者,可以在终端下输入如下命令来安装:
sudo apt-get install pgadmin3
你还可以通过系统->系统管理->新立德包管理器来安装这些包。
服务器基本设置
启动
sudo /etc/init.d/postgresql-8.4 start(10.04下安装的postgresql默认是8.4,若是10.10,则不用加版本号)
sudo /etc/init.d/postgresql-8.4 stop
设置密码
安装完毕,我们需要更改postgres用户的密码,否则我们就没法使用这个数据库服务器。以postgres这个系统用户的身份运行psql命令,在终端中输入如下:
sudo su postgres -c psql template1
这时候会出现新的提示符,输入下面两个命令,用新密码替换 :
ALTER USER postgres WITH PASSWORD ' ';
设置 postgres 用户的密码
sudo passwd postgres
而后输入自己的密码
创建数据库
创建第一个数据库,我们把它命名为"mydb",先输入:
su postgres
转入 postgres 用户.
用这样的方试会报错
sudo su postgres -c createdb mydb
转为 postgres 用户登陆后,执行
createdb mydb
使用pgAdmin III图形界面客户端
要了解PostgreSQL能干些什么,你首先要学会使用一个图形界面的客户端,在终端中输入:
pgadmin3
你现在停留在pgAdmin III的主界面,点击 "添加数据库连接" 按钮(在左上方)。弹出一个新的对话框,输入地址127.0.0.1,服务器描述,默认数据库"mydb" 和你的密码。
通过这个图形界面,你可以新建数据库,表和其他对象;查询数据库,添加数据,执行SQL语句等。用pgAdmin 3连接
效果图
管理数据库服务器
管理用户和权限
PostgreSQL没有一个简单的管理用户的方法 ,首先你必需编辑/etc/postgres/pg_hba.conf 并修改它的默认配置(默认配置的安全性非常高),你希望 postgres 来管理它的用户(和系统用户无关),你需要添加如下几行:
8
# TYPE DATABASE USER IP-ADDRESS IP-MASK METHOD
# rezo local
host all all 10.0.0.0 255.255.255.0 password
8
它的意思是通过你的本地网络(10.0.0.0/24要替换为你的本地网络 !), postgres用户可以以传统的”用户名+密码“的方式连接到数据库。
创建一个数据库,并创建一个对该数据库拥有所有权限的用户,可以使用如下命令:
sudo su postgres -c createuser -D -A -P myuser
sudo su postgres -c createdb -O myuser mydb
第一个命令是创建一个新用户,这个用户没有创建数据库的权限(-D),没有新建用户的权限(-A)。创建用户时会提示你输入密码。第二个命令是创建一个数据库'mydb ,以 'myuser' 作为它的所有者。

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