#Instructions

#This application will read roster data in JSON format, parse the file, and then produce an SQLite database that

#contains a User, Course, and Member table and populate the tables from the data file.

#You can base your solution on this code: http://www.pythonlearn.com/code/roster.py - this code is incomplete as you

#need to modify the program to store the role column in the Member table to complete the assignment.

#Each student gets their own file for the assignment. Download this file and save it as roster_data.json.

#Move the downloaded file into the same folder as your roster.py program.

#Once you have made the necessary changes to the program and it has been run successfully reading the above JSON data,

#run the following SQL command:

#SELECT hex(User.name || Course.title || Member.role ) AS X FROM

# User JOIN Member JOIN Course

# ON User.id = Member.user_id AND Member.course_id = Course.id

# ORDER BY X

#Find the first row in the resulting record set and enter the long string that looks like 53656C696E613333.

import json

import sqlite3

conn = sqlite3.connect('rosterdb.sqlite')

cur = conn.cursor()

# Do some setup

cur.executescript('''

DROP TABLE IF EXISTS User;

DROP TABLE IF EXISTS Member;

DROP TABLE IF EXISTS Course;

CREATE TABLE User (

id INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT UNIQUE,

name TEXT UNIQUE

);

CREATE TABLE Course (

id INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT UNIQUE,

title TEXT UNIQUE

);

CREATE TABLE Member (

user_id INTEGER,

course_id INTEGER,

role INTEGER,

PRIMARY KEY (user_id, course_id)

)

''')

fname = raw_input('Enter file name: ')

if ( len(fname) < 1 ) : fname = 'roster_data.json'

# [

# [ "Charley", "si110", 1 ],

# [ "Mea", "si110", 0 ],

str_data = open(fname).read()

json_data = json.loads(str_data)

for entry in json_data:

name = entry[0];

title = entry[1];

role = entry[2];

print name, title, role

cur.execute('''INSERT OR IGNORE INTO User (name)

VALUES ( ? )''', ( name, ) )

cur.execute('SELECT id FROM User WHERE name = ? ', (name, ))

user_id = cur.fetchone()[0]

cur.execute('''INSERT OR IGNORE INTO Course (title)

VALUES ( ? )''', ( title, ) )

cur.execute('SELECT id FROM Course WHERE title = ? ', (title, ))

course_id = cur.fetchone()[0]

cur.execute('''INSERT OR REPLACE INTO Member

(user_id, course_id, role) VALUES ( ?, ?, ? )''',

( user_id, course_id, role ) )

conn.commit()