It appears that there is currently two/three gem packages for using postgresql with ruby: postgres, ruby-pg, and pg - and from what I can make out, they’re all maintained by the same team now, (postgres was the original package, but it got abandoned - ruby-pg and pg are the replacements). As such, i’ll go with the newer ruby-pg gem…

sudo env ARCHFLAGS="-arch i386" gem install \
 ruby-pg -- \
 --with-pgsql-lib=/opt/local/lib/postgresql83 \
 --with-pgsql-include=/opt/local/include/postgresql83

Then finally, when writing the database.yml entry for connecting to postgresql, we have to define our adapter as follows:

development:
  adapter: postgresql
  database: test_dev
  encoding: unicode
  host: localhost
  user: XXXXX
  password: XXXXX
  timeout: 5000

Setting Up Our Environment

Using a text editor of your choice, add the following lines to the bottom of the /etc/profile file (you’ll need to be an administrator to do this):

# MacPorts
export PATH=/opt/local/bin:/opt/local/sbin:$PATH
 
# PostgreSQL
export PATH=/opt/local/lib/postgresql83/bin:$PATH

Now before we move on, make sure that you have MacPorts installed.

Installing PostgreSQL with MacPorts

I like MacPorts - it makes installing general Unix packages and keeping them up-to-date a snap. As such, we’ll use it to do the heavy lifting for installing PostgreSQL. Open up a terminal and hit up the following command:

sudo port install postgresql83 postgresql83-server

Sit back and wait a while… That’s the basic install done.

Now to configure it, do the following:

sudo mkdir -p /opt/local/var/db/postgresql83/defaultdb
sudo chown postgres:postgres /opt/local/var/db/postgresql83/defaultdb
sudo su postgres -c '/opt/local/lib/postgresql83/bin/initdb -D /opt/local/var/db/postgresql83/defaultdb'

This installs a default database instance for us to be getting on with. Next, run this command to get PostgreSQL to start on system boot:

sudo launchctl load -w /Library/LaunchDaemons/org.macports.postgresql83-server.plist

Reboot your Mac.

Creating a User Account and Database

Once your Mac is back up, we finally need to create an account for us to use (substitute ‘daz’ for your username)…

createuser --superuser daz -U postgres

Now a database to play with…

createdb test_db

Admin Your Database with pgAdmin 3

Download pgAdmin, then run the following commands to set up some functions that allows pgAdmin to collect statistics about your databases:

cd /opt/local/share/postgresql83/contrib/
sudo su postgres -c psql < adminpack.sql

That’s it - job done!¹

This quick walk-through are my notes for installing the PostgreSQL database server and the PgAdmin administration application on Ubuntu Linux, and also set up the server so it allows access to other PC’s on your network.

Before we move on, this guide was tested on the current release of Ubuntu Linux, (8.04 - Hardy Heron) and PostgreSQL 8.3, but it should also be applicable to older versions (of Ubuntu and PostgreSQL) and other Debian based distros.

Right for the basic installation, at the command-line, enter the following commands (or search for the listed packages in synaptic if you prefer that way of working):

$ sudo apt-get install postgresql postgresql-client postgresql-contrib
$ sudo apt-get install pgadmin3

This installs the database server/client, some extra utility scripts and the pgAdmin GUI application for working with the database.

Now we need to reset the password for the ‘postgres’ admin account for the server, so we can use this for all of the system administration tasks. Type the following at the command-line (substitute in the password you want to use for your administrator account):

$ sudo su postgres -c psql template1
template1=# ALTER USER postgres WITH PASSWORD 'password';
template1=# \q

That alters the password for within the database, now we need to do the same for the unix user ‘postgres’:

$ sudo passwd -d postgres
$ sudo su postgres -c passwd

Now enter the same password that you used previously.

Then, from here on in we can use both pgAdmin and command-line access (as the postgres user) to run the database server. But before you jump into pgAdmin we should set-up the PostgreSQL admin pack that enables better logging and monitoring within pgAdmin. Run the following at the command-line:

$ sudo su postgres -c psql < /usr/share/postgresql/8.3/contrib/adminpack.sql

Finally, we need to open up the server so that we can access and use it remotely - unless you only want to access the database on the local machine. To do this, first, we need to edit the postgresql.conf file:

$ sudo gedit /etc/postgresql/8.3/main/postgresql.conf

Now, to edit a couple of lines in the ‘Connections and Authentication’ section…

Change the line:

#listen_addresses = 'localhost'

to

listen_addresses = '*'

and also change the line:

#password_encryption = on

to

password_encryption = on

Then save the file and close gedit.

Now for the final step, we must define who can access the server. This is all done using the pg_hba.conf file.¹

$ sudo gedit /etc/postgresql/8.3/main/pg_hba.conf

Comment out, or delete the current contents of the file, then add this text to the bottom of the file:

# DO NOT DISABLE!
# If you change this first entry you will need to make sure that the
# database
# super user can access the database using some other method.
# Noninteractive
# access to all databases is required during automatic maintenance
# (autovacuum, daily cronjob, replication, and similar tasks).
#
# Database administrative login by UNIX sockets
local   all         postgres                          ident sameuser
# TYPE  DATABASE    USER        CIDR-ADDRESS          METHOD

# "local" is for Unix domain socket connections only
local   all         all                               md5
# IPv4 local connections:
host    all         all         127.0.0.1/32          md5
# IPv6 local connections:
host    all         all         ::1/128               md5

# Connections for all PCs on the subnet
#
# TYPE DATABASE USER IP-ADDRESS IP-MASK METHOD
host    all         all         [ip address]          [subnet mask]  md5

and in the last line, add in your subnet mask (i.e. 255.255.255.0) and the IP address of the machine that you would like to access your server (i.e. 138.250.192.115). However, if you would like to enable access to a range of IP addresses, just substitute the last number for a zero and all machines within that range will be allowed access (i.e. 138.250.192.0 would allow all machines with an IP address 138.250.192.x to use the database server).

That’s it, now all you have to do is restart the server:

$ sudo /etc/init.d/postgresql-8.3 restart

And all should be working.

phpPgAdmin is a web based GUI for administrating a PostgreSQL database server.

Here’s some quick notes on getting it installed easily on Ubuntu 7.10…

In the terminal enter the following:

$ sudo apt-get install phppgadmin

This will set up and install all of the phpPgAdmin packages. It will also set-up and configure Apache and php5 for you too if you haven’t installed these already.

Next we need to create a symlink to phpPgAdmin so that Apache can find it:

$ sudo ln -s /etc/phppgadmin/apache.conf /etc/apache2/conf.d/phppgadmin.conf

Now if you navigate to http://localhost/phppgadmin you should be greeted with the phpPgAdmin screen. If your user account has a PostgreSQL account however, you will be logged in automagically.

Optionally, if you would like to be able to use the phpPgAdmin interface as the default ‘postgres’ administration account,¹ you will need to do the following²…

$ sudo gedit /usr/share/phppgadmin/conf/config.inc.php

Now find and change the following line

$conf['extra_login_security'] = true;

to

$conf['extra_login_security'] = false;

Save and close gedit. Now all you need to do is restart Apache.

$ sudo /etc/init.d/apache2 reload

Now if you head on over to http://localhost/phppgadmin all should be ready for you.

Create our new user:

$ sudo su postgres -c createuser daz

Then you have to give this new user role a name (I called it daz), and then say ‘y’ to the question “Shall the new role be a superuser?” if you want the user to be an administrator.

Give the user a database password (this does not have to be the same as their unix password):

$ sudo su postgres -c psql
postgres=# ALTER USER daz WITH PASSWORD 'mypassword';
postgres=# \q

Finally, give the new user a database to play with:

$ sudo su postgres -c createdb daz

Pretty straight forward…

This quick walk-through are my notes for installing the PostgreSQL database server and the PgAdmin administration application on Ubuntu Linux, and also set up the server so it allows access to other PC’s on your network.

Before we move on, this guide was tested on the current release of Ubuntu Linux, (7.10 - Gutsy Gibbon) and PostgreSQL 8.2, but it should also be applicable to older versions (of Ubuntu and PostgreSQL) and other Debian based distros.

Right for the basic installation, at the command-line, enter the following commands (or search for the listed packages in synaptic if you prefer that way of working):

$ sudo apt-get install postgresql postgresql-client postgresql-contrib
$ sudo apt-get install pgadmin3

This installs the database server/client, some extra utility scripts and the pgAdmin GUI application for working with the database.

Now we need to reset the password for the ‘postgres’ admin account for the server, so we can use this for all of the system administration tasks. Type the following at the command-line (substitute in the password you want to use for your administrator account):

$ sudo su postgres -c psql template1
template1=# ALTER USER postgres WITH PASSWORD 'password';
template1=# \q

That alters the password for within the database, now we need to do the same for the unix user ‘postgres’:

$ sudo passwd -d postgres
$ sudo su postgres -c passwd

Now enter the same password that you used previously.

Then, from here on in we can use both pgAdmin and command-line access (as the postgres user) to run the database server. But before you jump into pgAdmin we should set-up the PostgreSQL admin pack that enables better logging and monitoring within pgAdmin. Run the following at the command-line:

$ sudo su postgres -c psql < /usr/share/postgresql/8.2/contrib/adminpack.sql

Finally, we need to open up the server so that we can access and use it remotely - unless you only want to access the database on the local machine. To do this, first, we need to edit the postgresql.conf file:

$ sudo gedit /etc/postgresql/8.2/main/postgresql.conf

Now, to edit a couple of lines in the ‘Connections and Authentication’ section…

Change the line:

#listen_addresses = 'localhost'

to

listen_addresses = '*'

and also change the line:

#password_encryption = on

to

password_encryption = on

Then save the file and close gedit.

Now for the final step, we must define who can access the server. This is all done using the pg_hba.conf file.¹

$ sudo gedit /etc/postgresql/8.2/main/pg_hba.conf

Comment out, or delete the current contents of the file, then add this text to the bottom of the file:

# DO NOT DISABLE!


If you change this first entry you will need to make sure that the

database

super user can access the database using some other method.

Noninteractive

access to all databases is required during automatic maintenance

(autovacuum, daily cronjob, replication, and similar tasks).

#

Database administrative login by UNIX sockets

local   all         postgres                          ident sameuser

TYPE  DATABASE    USER        CIDR-ADDRESS          METHOD

"local" is for Unix domain socket connections only

local   all         all                               md5

IPv4 local connections:

host    all         all         127.0.0.1/32          md5

IPv6 local connections:

host    all         all         ::1/128               md5

Connections for all PCs on the subnet

#

TYPE DATABASE USER IP-ADDRESS IP-MASK METHOD

host    all         all         [ip address]          [subnet mask]  md5

and in the last line, add in your subnet mask (i.e. 255.255.255.0) and the IP address of the machine that you would like to access your server (i.e. 138.250.192.115). However, if you would like to enable access to a range of IP addresses, just substitute the last number for a zero and all machines within that range will be allowed access (i.e. 138.250.192.0 would allow all machines with an IP address 138.250.192.x to use the database server).

That’s it, now all you have to do is restart the server:

$ sudo /etc/init.d/postgresql-8.2 restart

And all should be working.