parallelized COPY in postgres

parallelcopy.py

import multiprocessing
import subprocess
from glob import glob
import os

fields = ["field1", "field2", "field3"]

def work(fname):
    print "starting %s" % fname
    fname = os.path.abspath(fname)
    cmd2 = "\COPY flights(%s) FROM '%s' WITH DELIMITER ',' NULL AS '' CSV HEADER;" % (",".join(fields), fname)
    retval = subprocess.call(['psql', '-U', 'postgres', '-d', 'takeoff', '-c', cmd2 ], shell=False)
    print "ending %s" % fname
    return retval

if __name__ == '__main__':
    count = multiprocessing.cpu_count()
    pool = multiprocessing.Pool(processes=count)
    print pool.map(work, glob('flights/*.csv'))