SQLiteにPythonでUDFを追加するやつ

sqlite-ex.py

#!/usr/bin/env python
# -*- coding:utf-8 -*-
import sqlite3
import numpy as np

class Median:
    def __init__(self):
        self.values = []
    def step(self, value):
        self.values.append(value)
    def finalize(self):
        return np.median(self.values)

def main(file, query):
    con = sqlite3.connect(file, isolation_level=None)
    con.create_aggregate("median", 1, Median)
    c = con.cursor()
    c.execute(query)
    l = []
    for row in c:
        print u'\t'.join(unicode(x) for x in row)

import sys
main(sys.argv[1], sys.argv[2])