PostgreSQL 创建一个新的database system
第一步：su postgres
第二步：bash-4.2$ /usr/pgsql-9.1/bin/initdb -D /var/lib/pgsql/9.1/data/ ，， 回车后出现如下信息
The files belonging to this database system will be owned by user "postgres".
This user must also own the server process.
The database cluster will be initialized with locale en_US.UTF-8.
The default database encoding has accordingly been set to UTF8.
The default text search configuration will be set to "english".
fixing permissions on existing directory /var/lib/pgsql/9.1/data ... ok
creating subdirectories ... ok
selecting default max_connections ... 100
selecting default shared_buffers ... 24MB
creating configuration files ... ok
creating template1 database in /var/lib/pgsql/9.1/data/base/1 ... ok
initializing pg_authid ... ok
initializing dependencies ... ok
creating system views ... ok
loading system objects' descriptions ... ok
creating collations ... ok
creating conversions ... ok
creating dictionaries ... ok
setting privileges on built-in objects ... ok
creating information schema ... ok
loading PL/pgSQL server-side language ... ok
vacuuming database template1 ... ok
copying template1 to template0 ... ok
copying template1 to postgres ... ok
WARNING: enabling "trust" authentication for local connections
You can change this by editing pg_hba.conf or using the -A option the
next time you run initdb.
Success. You can now start the database server using:
/usr/pgsql-9.1/bin/postgres -D /var/lib/pgsql/9.1/data
or
/usr/pgsql-9.1/bin/pg_ctl -D /var/lib/pgsql/9.1/data -l logfile start
第三步：用上边两个命令中的一个启动服务
第四步：创建一个用户（user）
bash-4.2$ createuser qiaoning -P
Enter password for new role: //输入密码
Enter it again: //再次输入密码
Shall the new role be a superuser? (y/n) n //是否是超级用户，选否
Shall the new role be allowed to create databases? (y/n) y //该用户是否可以创建数据库，选是
Shall the new role be allowed to create more new roles? (y/n) n //该用户是否可以创建新的角色，选否
第五步：创建数据库
bash-4.2$ createdb qiaoning --owner=qiaoning //第一个qiaoning是数据库名称，第二个qiaoning是数据库的拥有者
以上步骤完成后需要修改一些配置文件（主要是访问权限的设置）
第一步：进入刚才创建的database system所在的目录，即：/var/lib/pgsql/9.1/data/
