Install plr extension in postgresql

install R

sudo yum install epel-release
sudo yum install R

## make sure postgresql94-devel is installed, so we can use PGXS
sudo yum install postgresql94-devel

install plr

wget https://github.com/jconway/plr/archive/REL8_3_0_16.zip
unzip REL*
cd plr-REL8_3_0_16
PATH=/usr/pgsql-9.4/bin/:$PATH; USE_PGXS=1 make
echo 'PATH=/usr/pgsql-9.4/bin/:$PATH; USE_PGXS=1 make install' | sudo sh
# plr install complete

create extension in db

psql -U postgres -d db_name -c 'CREATE EXTENSION plr;'