SQlite WAL-mode in python

Reader

import sqlite3
from time import sleep
conn = sqlite3.connect('example.db', isolation_level=None)

c = conn.cursor()
while True:
    c.execute("SELECT * FROM statistics")
    try:
        print '**'
        print c.fetchone()
    except:
        pass
    sleep(3)

Writer

import sqlite3
from time import sleep
import os

if os.path.exists('example.db'):
    os.remove('example.db')

conn = sqlite3.connect('example.db', isolation_level=None)
c = conn.cursor()
c.execute('PRAGMA journal_mode=wal')
print c.fetchone()
c.execute("CREATE TABLE statistics (stat1 real, stat2 real)")

stat1 = 0
stat2 = 0.0
while True:
    stat1 += 1
    stat2 += 0.1
    cmd = "INSERT INTO statistics VALUES (%d,%f)" % (stat1, stat2)
    print cmd
    c.execute(cmd)
    #conn.commit()
    c.execute("PRAGMA wal_checkpoint=FULL")
    sleep(0.25)

References
https://stackoverflow.com/questions/30821179/sqlite-wal-mode-in-python-concurrency-with-one-writer-and-one-reader
https://sqlite.org/wal.html

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