http://joeconway.com/doc/plr-US.pdf
=== Sample Function Code in PostgreSQL ===
Inside a database (ex) tigertest):
CREATE OR REPLACE FUNCTION r_max (integer, integer) RETURNS integer AS ’
if (arg1 > arg2)
return(arg1)
else
return(arg2)
’ LANGUAGE ’plr’ STRICT;
==Installing PL/R on the dbase server==