In order to create a databases, the PostgreSQL
server must be up and running (see Section 3.3).
Databases are created with the query language command
CREATE DATABASE:
CREATE DATABASE name
where name follows the usual rules for SQL identifiers.
The current user automatically becomes
the owner of the new database. It is the privilege of the owner of
a database to remove it later on (which also removes all the
objects in it, even if they have a different owner).
The creation of databases is a restricted operation. See Section 4.2 for how to grant permission.
Since you need to be connected to the database server in order to
execute the CREATE DATABASE command, the
question remains how the first database at any given
site can be created. The first database is always created by the
initdb command when the data storage area is
initialized. (See Section 3.2.) By convention
this database is called template1. So to create the
first "real" database you can connect to
template1.
The name "template1" is no accident: When a new
database is created, the template database is essentially cloned.
This means that any changes you make in template1 are
propagated to all subsequently created databases. This implies that
you should not use the template database for real work, but when
used judiciously this feature can be convenient. More details
appear in Section 5.3.
As an extra convenience, there is also a program that you can
execute from the shell to create new databases,
createdb.
createdb dbname
createdb does no magic. It connects to the template1
database and issues the CREATE DATABASE command,
exactly as described above. It uses the psql program
internally. The reference page on createdb contains the invocation
details. Note that createdb without any arguments will create
a database with the current user name, which may or may not be what
you want.
Note: Chapter 6 contains information about
how to restrict who can connect to a given database.
Sometimes you want to create a database for someone else. That
user should become the owner of the new database, so he can
configure and manage it himself. To achieve that, use one of the
following commands:
CREATE DATABASE dbname OWNER username;
from the SQL environment, or
createdb -O username dbname
You must be a superuser to be allowed to create a database for
someone else.