database_extractor.py

import sqlite3
import json
from datetime import datetime

#data set is for the time frame of month of may 2015
timeframe = '2015-05'
sql_transaction = []

connection = sqlite3.connect('{}.db'.format(timeframe))
c = connection.cursor()

def create_table():
    c.execute("""CREATE TABLE IF NOT EXISTS parent_reply
    (parent_id TEXT PRIMARY KEY, comment_id TET UNIQUE, parent TEXT, comment TEXT, subreddit TEXT, unix INT, score INT)""")

def format_data(data):
    data = data.replace("\n", " newlinechar ").replace("\r", " newlinechar ").replace('"', "'")
    return data


def acceptable(data):
    if len(data.split(' ')) > 50 or len(data) < 1:
        return False
    elif len(data) > 1000:
        return False
    elif data == '[deleted]' or data == '[removed]':
        return False
    else:
        return True


def find_parent(pid):
    try:
        sql = "SELECT comment FROM parent_reply WHERE comment_id = '{}' LIMIT 1".format(pid)
        c.execute(sql)
        result = c.fetchone()
        if result != None:
            return result[0]
            #there is no need to put [0] but it returns a list of comments,
            #if we were to call select comments,score in the quiry we would need [0]
        else:
            return False
    except Exception as e:
        #print("find_parent",e)
        return False

def find_existing_score(pid):
    try:
        sql = "SELECT score FROM parent_reply WHERE parent_id = '{}' LIMIT 1".format(pid)
        c.execute(sql)
        result = c.fetchone()
        if result != None:
            return result[0]
            #there is no need to put [0] but it returns a list of comments,
            #if we were to call select comments,score in the quiry we would need [0]
        else:
            return False
    except Exception as e:
        #print("find_parent",e)
        return False


def transaction_bldr(sql):
    global sql_transaction
    sql_transaction.append(sql)
    if len(sql_transaction) > 1000:
        c.execute('BEGIN TRANSACTION')
        for s in sql_transaction:
            try:
                c.execute(s)
            except:
                pass
        connection.commit()
        sql_transaction = []

def sql_insert_replace_comment(commentid, parentid, parent, comment, subreddit, time, score):
    try:
        sql = """UPDATE parent_reply SET parent_id = ?, comment_id = ?, parent = ?, comment = ?, subreddit = ?, unix = ?, score = ? WHERE parent_id =?;""".format(parentid, commentid, parent, comment, subreddit, int(time), score, parentid)
        transaction_bldr(sql)
    except Exception as e:
        print('s-UPDATE insertion', str(e))

def sql_insert_has_parent(commentid,parentid,parent,comment,subreddit,time,score):
    try:
        sql = """INSERT INTO parent_reply (parent_id, comment_id, parent, comment, subreddit, unix, score) VALUES ("{}","{}","{}","{}","{}",{},{});""".format(parentid, commentid, parent, comment, subreddit, int(time), score)
        transaction_bldr(sql)
    except Exception as e:
        print('s-PARENT insertion',str(e))

def sql_insert_no_parent(commentid,parentid,comment,subreddit,time,score):
    try:
        sql = """INSERT INTO parent_reply (parent_id, comment_id, comment, subreddit, unix, score) VALUES ("{}","{}","{}","{}",{},{});""".format(parentid, commentid, comment, subreddit, int(time), score)
        transaction_bldr(sql)
    except Exception as e:
        print('s-NOPARENT insertion',str(e))


if __name__ == "__main__":
    create_table()
    row_counter = 0
    paired_rows = 0

    with open("/mnt/c/Users/sanjj/Desktop/AMRITA/S3/Projects/python/RC_{}".format(timeframe), buffering = 1000) as f:
        for row in f:
            row_counter += 1
            row = json.loads(row)
            parent_id = row['parent_id']
            body = format_data(row['body'])
            created_utc = row['created_utc']
            score = row['score']
            subreddit = row['subreddit']
            comment_id = row['name']
            parent_data = find_parent(parent_id)

            #giving a minimal threshold for
            #the number of times people gave the comment a thmbs up
            if score >= 2:
                if acceptable(body):
                    existing_comment_score = find_existing_score(parent_id)
                    if existing_comment_score:
                        if score >existing_comment_score:
                            sql_insert_replace_comment(comment_id, parent_id, parent_data, body, subreddit, created_utc, score)
                    else:
                        if parent_data:
                            sql_insert_has_parent(comment_id, parent_id, parent_data, body, subreddit, created_utc, score)
                            paired_rows += 1
                        else:
                            sql_insert_no_parent(comment_id, parent_id, body, subreddit, created_utc, score)

            if row_counter % 100000 == 0:
                print("Total Rows Read: {}, Paired Rows: {}, Time: {}".format(row_counter, paired_rows, str(datetime.now())))