[Tutor] Good Taste Question: Using SQLite3 in Python

[Jugurtha Hadjar]

Hello, all..

I have a class with methods that access a database (SQLite3). I have 
included an excerpt showin reading and writing and would like to know if 
I'm doing it right. (i.e: Is it bad code and what to improve).

Here are some improvements and my rationale (check my thinking):

- Initially, each method had its SQL statement(s) inside, but I grouped 
all statements in a dictionary, with operations as keys, as a class 
'constant' as per previous advice on this mailing list.

- Each method used sqlite3 module on its own, but it was repetitive so I 
put that part in its own method `init_db` that returns a tuple 
consisting in a connection and a cursor.

- Sometimes there was an exception raised, so I used `try` in `init_db`.

- Methods closed the connection themselves, so I used `with` in 
`init_db` instead of `try`, as it would close the connection 
automatically and rollback (I hope I'm not making this up).

Here's the excerpt (`DB_FILES` and `QUERIES` are not included here for 
more clarity).

Thank you.



	def __init__(self, phone):

		# Get preliminary information on user and make them
		# available.

		self.phone = phone
		self.known = self.find()
		
		if self.known:
			self.balance = self.get_balance()
		else:
			self.balance = None

	def init_db(self):
		with sqlite3.connect(self.DB_FILE) as conn:
			return conn, conn.cursor()

	def find(self):
		'''Find the phone in the users database.'''
		
		(__, cursor) = self.init_db()
		try:
			cursor.execute(
				self.QUERIES['FIND_PHONE'],
				(self.phone,)
			)
			found = cursor.fetchone()
			return True if found else False
		except Exception as e:
			return self.ERROR.format(e.args[0])

	def create(self, seed_balance):
		''' Create a database entry for the sender.'''

		conn, cursor = self.init_db()
		try:
			cursor.execute(
				self.QUERIES['CREATE'],
				(self.phone, seed_balance)
			)
			conn.commit()
		except Exception as e:
			return self.ERROR.format(e.args[0])




-- 
~Jugurtha Hadjar,