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SQL Database file not showing up in folder?

I am trying to create a database file using the following code:
def dbconnect():
try:
sqliteConnection = sqlite3.connect('SQLite_Python.db')
cursor = sqliteConnection.cursor()
print("Database created and Successfully Connected to SQLite")
sqlite_select_Query = "select sqlite_version();"
cursor.execute(sqlite_select_Query)
record = cursor.fetchall()
print("SQLite Database Version is: ", record)
cursor.close()
except sqlite3.Error as error:
print("Error while connecting to sqlite", error)
finally:
if sqliteConnection:
sqliteConnection.close()
print("The SQLite connection is closed")
conn = dbconnect()
conn.close()
yet when I run the code, although there are no file errors, it doesnt print anything or create a SQL file in the folder of the python code.
I can't seem to figure out what is going wrong.

Running a python script with prepared statement gives me no errors but doesn't do what I expect [duplicate]

This question already has answers here:
psycopg2 not actually inserting data
(2 answers)
Closed 2 months ago.
I am running this python code to read in quotes from a file and then insert each quote into a table in my database. When I run the script in my terminal there are no errors but when I go to the database table I tried to insert to it tells me there are 0 rows.
#!/usr/bin/python
import psycopg2
import re
from config import config
conn = psycopg2.connect(
host="localhost",
database="favorite_quotes",
user="postgres",
password="???")
data = None
with open('file.txt', 'r') as file:
data = file.read()
list_of_strings = re.findall('“(.+?)” \(.+?\)', data, re.DOTALL)
def insert_quotes():
""" Connect to the PostgreSQL database server """
conn = None
try:
# read connection parameters
params = config()
# connect to the PostgreSQL server
print('Connecting to the PostgreSQL database...')
conn = psycopg2.connect(**params)
# create a cursor
cur = conn.cursor()
for str in list_of_strings:
cur.execute("INSERT INTO the_courage_to_be_disliked (quote) VALUES (%s)", [str])
# execute a statement
# dblist = list(cur.fetchone())
# quotes = []
# for row in cur:
# quotes.append(row[1])
# return quotes
# close the communication with the PostgreSQL
cur.close()
except (Exception, psycopg2.DatabaseError) as error:
print(error)
finally:
if conn is not None:
conn.close()
print('Database connection closed.')
if __name__ == '__main__':
insert_quotes()

You aren't committing your inserts, so they won't be visible from outside the current connection, and will be implicitly rolled back when the connection is closed.
TL;DR, add a call to conn.comimt() before calling conn.close().

What is a good strategy for database cennection in continuous Python script?

I have continuous Python script that parses certain websites or XML's every 30 second and adds records o database if it turns out, there is something new.
First, I was just connecting to database every time which I knew, wasn't ideal way how to do it. i had something like this:
def job():
try:
cnx = mysql.connector.connect(user=DB_USER, password=DB_PASSWORD, host='XYZ', database=DB_NAME)
cursor = cnx.cursor()
# CALLS OF PARSERS:
run_parser1(cnx, cursor)
run_parser2(cnx, cursor)
# etc...
except Exception as e:
cursor.close()
cnx.close()
schedule.every(30).seconds.do(job)
while 1:
schedule.run_pending()
time.sleep(1)
Now I edited my code so connection is open until there is an exception either in connecting to database or in parsing:
try:
cnx = mysql.connector.connect(user=DB_USER, password=DB_PASSWORD, host='XYZ', database=DB_NAME)
cursor = cnx.cursor()
except Exception as e:
cursor.close()
cnx.close()
def job():
try:
alert_list = CAPParser(getxml()).as_dict()
# CALL OF PARSERS:
run_parser1(cnx, cursor)
run_parser2(cnx, cursor)
# etc...
except Exception as e:
cursor.close()
cnx.close()
schedule.every(30).seconds.do(job)
while 1:
schedule.run_pending()
time.sleep(1)
However, there is problem. While I know it's secure way to do it, it means that I need to restart script several times per day. There are a lot of exceptions either from lost database connection or unavailable URL's of parsed sites or files.
Any advice how to find better solution?

You could try to create a function which verifies if the cnx is open and if it's not, recreate it. Something like:
def job():
global cnx
global cursor
if not cnx.is_connected(): # Uses ping to verify connection
try:
cnx = mysql.connector.connect(user=DB_USER, password=DB_PASSWORD, host='XYZ', database=DB_NAME)
cursor = cnx.cursor()
except Exception as e:
cursor.close()
cnx.close()
# You can do this try in a while with a delay to keep retrying to connect
... # job here

PYTHON MYSQL doesn't work second time

Am receiving json data (from an other python script) to put inside MYSQL database, the code work fine the first time but the second time I got this error:
raise errors.OperationalError("MySQL Connection not available.")
mysql.connector.errors.OperationalError: MySQL Connection not available.
For troubleshooting am sending always the same data, but it still write an error the second time.
I tried also from information found on furums to place : cur = mydb.cursor() at diferents places but I have never been able to get this code work the second time.
There is my code :
import mysql.connector
import json
mydb = mysql.connector.connect(
host="localhost",
user="***",
passwd="***",
database="***"
)
def DATA_REPARTITION(Topic, jsonData):
if Topic == "test":
#print ("Start")
INSERT_DEBIT(jsonData)
def INSERT_DEBIT(jsonData):
cur = mydb.cursor()
#Read json from MQTT
print("Start read data to insert")
json_Dict = json.loads(jsonData)
debit = json_Dict['debit']
print("I send")
print(debit)
#Insert into DB Table
sql = ("INSERT INTO debit (data_debit) VALUES (%s)")
val=debit,
cur.execute(sql,val)
mydb.commit()
print(cur.rowcount, "record inserted.")
cur.close()
mydb.close()
Thanks for your help!

You only open your database connection once, at the start of the script, and you close that connection after making the first insert. Hence, second and subsequent inserts are failing. You should create a helper function which returns a database connection, and then call it each time you want to do DML:
def getConnection():
mydb = mysql.connector.connect(
host="localhost",
user="***",
passwd="***",
database="***")
return mydb
def INSERT_DEBIT(jsonData):
mydb = getConnection()
cur = mydb.cursor()
# Read json from MQTT
# rest of your code here...
cur.close()
mydb.close()

How to handle exception in the "finally" block?

Given the following Python code:
# Use impyla package to access Impala
from impala.dbapi import connect
import logging
def process():
conn = connect(host=host, port=port) # Mocking host and port
try:
cursor = conn.cursor()
# Execute query and fetch result
except:
loggin.error("Task failed with some exception")
finally:
cursor.close() # Exception here!
conn.close()
The connection to Impala was created. But there was an exception in cursor.close() due to Impala timeout.
What is the proper way to close the cursor and conn given the latent exception?

You have to nest the try-blocks:
def process():
conn = connect(host=host, port=port) # Mocking host and port
try:
cursor = conn.cursor()
try:
# Execute query and fetch result
finally:
# here cursor may fail
cursor.close()
except:
loggin.error("Task failed with some exception")
finally:
conn.close()
To avoid such try-finally-blocks, you can use the with-statement:
def process():
conn = connect(host=host, port=port) # Mocking host and port
try:
with conn.cursor() as cursor:
# Execute query and fetch result
# cursor is automatically closed
except:
loggin.error("Task failed with some exception")
finally:
conn.close()