Tag: kubuntu

Correctly Uninstall PostgreSQL

Uninstalling PostgreSQL may leave some undesired files. Here’s how to purge it:

First, uninstall all packages from PostgreSQL from the system using

sudo apt-get --purge remove postgresql\*

Then remove all the configuration and library stuff

sudo rm -r /etc/postgresql/
sudo rm -r /etc/postgresql-common/
sudo rm -r /var/lib/postgresql/

And finally, remove the user and group

sudo userdel -r postgres
sudo groupdel postgres

Upgrade PostgreSQL from 9.1 to 9.3 on Kubuntu

This seven steps will perform the upgrade of PostgreSQL from version 9.1 to version 9.3.
This also works in Ubuntu and it can also be used to upgrade between any version numbers.

To upgrade between any versions, just changed the 9.1 for the legacy version number and the 9.3 for the new version number.

First install the necessary dependencies

sudo apt-get update
sudo apt-get -y install python-software-properties

Second, add the PostgreSQL repository

wget --quiet -O - https://www.postgresql.org/media/keys/ACCC4CF8.asc | sudo apt-key add -

Third, setup the repository

sudo sh -c 'echo "deb http://apt.postgresql.org/pub/repos/apt/ precise-pgdg main" >> /etc/apt/sources.list.d/postgresql.list'

Fourth, install PostgreSQL 9.3.

sudo apt-get install postgresql-9.3 postgresql-server-dev-9.3 postgresql-contrib-9.3

Fifth, perform the upgrade process.
The upgrade process is performed by having both servers running at the same time. Note that the new 9.3 version will run on a different port, 5433 as specified in the script bellow, and it will be set to the default port latter when the legacy version is uninstalled and the default port becomes available.

sudo su -l postgres
psql -d template1 -p 5433
CREATE EXTENSION IF NOT EXISTS hstore;
CREATE EXTENSION IF NOT EXISTS "uuid-ossp";
\q #logout from database
service postgresql stop
/usr/lib/postgresql/9.3/bin/pg_upgrade -b /usr/lib/postgresql/9.1/bin -B /usr/lib/postgresql/9.3/bin -d /var/lib/postgresql/9.1/main/ -D /var/lib/postgresql/9.3/main/ -O " -c config_file=/etc/postgresql/9.3/main/postgresql.conf" -o "-c config_file=/etc/postgresql/9.1/main/postgresql.conf"
exit # logout postgresql back to previous user

Sixth, remove the 9.1 version.

sudo apt-get remove postgresql-9.1

Seventh, set the new version server port back to the default value and restart the service.

sudo vim /etc/postgresql/9.3/main/postgresql.conf # find old port of 5433 and change it to 5432
sudo service postgresql restart

Install R on Kubuntu

Installing R on Kubuntu, or Ubuntu, with an editor is quite easy. The following steps will possibly work on the most common Linux distributions. Check the official information for more information.

To get R, start by updating the repositories and the get r-base:

$ sudo apt-get update
$ sudo apt-get install r-base

When one needs to develop a R package, the development stuff should also be installed:

$ sudo apt-get install r-base-dev r-recommended

As for an editor, one can use JGR. In order to use it, just follow the official installation under Linux.
JGR is Java based, so when there’s no Java installed, get it using:

$ sudo apt-get install sun-java6-jdk

To install JGR, it’s necessary to enable Java support in R:

$ sudo R CMD javareconf

And then install the JGR library:

$ sudo R
> install.packages('JGR')

After installed, run:

> library(JGR)
> JGR()

JGR has a small problem though, it has been installed as root and it seems unusable with any other user. One can set the correct user permissions for that.

Automating the startup of R with JGR is simple when using a shell script. Name it runr.sh and include:

R -f /home/myUser/bin/jgr.r

While the jgr.r file contains the JGR start commands

library(JGR)
JGR()

Now, running ./runr.sh starts R and JGR all in one.

There are alternatives to JGR. Check Tinn-R and R Commander.