#!/usr/bin/env ruby1.9.1 require 'pg' db = PG.connect( :dbname => 'test' ) db.exec "DROP TABLE IF EXISTS test" db.exec "CREATE TABLE test (a INTEGER, b BYTEA)" a = 42 b = [1, 2, 3] db.exec "INSERT INTO test(a, b) VALUES($1::int, $2::bytea)", [a, {:value => b.pack('N*'), :format => 1}] db.exec( "SELECT a::int, b::bytea FROM test LIMIT 1", [], 1 ) do |res| res.nfields.times do |i| puts "Field %d is: %s, a %s (%s) column from table %p" % [ i, res.fname( i ), db.exec( "SELECT format_type($1,$2)", [res.ftype(i), res.fmod(1)] ).getvalue(0,0), res.fformat( i ).zero? ? "string" : "binary", res.ftable( i ), ] end res.each do |row| puts "a = #{row['a'].inspect}" puts "a (unpacked) = #{row['a'].unpack('N*').inspect}" puts "b = #{row['b'].unpack('N*').inspect}" end end