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How to share a mysql connection that is inside a function?

I am a beginner in python and mysql. I have a small application written in Python that connects to remote mysql server. There is no issues to connect and fetch data. It works fine then the code is outside a function. As I want to close and open connections, execute different queries from several functions inside my application, I would like to be able to call a function to establish a connection or run a query as needed. It seems that when I create an connection, that connection can not be used outside the function. I would like to implement something like this:
mydbConnection():
....
mydbQuery():
....
connected = mydbConnection()
myslq = 'SELECT *.......'
result = mydbQuery(mysql)
And so on...
Thanks for any direction on this.

import mysql.connector
from mysql.connector import Error
def mydbConnection(host_name, user_name, user_password):
connection = None
try:
connection = mysql.connector.connect(
host=host_name,
user=user_name,
passwd=user_password
)
print("Connection to MySQL DB successful")
except Error as e:
print(f"The error '{e}' occurred")
return connection
connection = mydbConnection("localhost", "root", "")
In the above script, you define a function mydbConnection() that accepts three parameters:
host_name
user_name
user_password
The mysql.connector Python SQL module contains a method .connect() that you use in line 7 to connect to a MySQL database server. Once the connection is established, the connection object is returned to the calling function. Finally, in line 18 you call mydbConnection() with the host name, username, and password.
Now, to use this connect variable, here is a function:
def mydbQuery(connection, query):
cursor = connection.cursor()
try:
cursor.execute(query)
print("Database created successfully")
except Error as e:
print(f"The error '{e}' occurred")
To execute queries, you use the cursor object. The query to be executed is passed to cursor.execute() in string format.
Create a database named db for your social media app in the MySQL database server:
create_database_query = "CREATE DATABASE db"
mydbQuery(connection, create_database_query)

Connect to postgresql using python script (database URI) but detects 'conn' as string

I am using a simple python script to connect the postgresql and future will create the table into the postgresql just using the script.
My code is:
try:
conn = "postgresql://postgres:<password>#localhost:5432/<database_name>"
print('connected')
except:
print('not connected')
conn.close()
when I run python connect.py (my file name), it throws this error :
Instance of 'str' has no 'commit' member
pretty sure is because it detects 'conn' as a string instead of database connection. I've followed this documentation (33.1.1.2) but now sure if Im doing it right. How to correct this code so it will connect the script to my postgresql server instead of just detects it as a string?
p/s: Im quite new to this.

You are trying to call a method on a string object.
Instead you should establish a connection to your db at first.
I don't know a driver which allows the use of a full connection string but you can use psycopg2 which is a common python driver for PostgreSQL.
After installing psycopg2 you can do the following to establish a connection and request your database
import psycopg2
try:
connection = psycopg2.connect(user = "yourUser",
password = "yourPassword",
host = "serverHost",
port = "serverPort",
database = "databaseName")
cursor = connection.cursor()
except (Exception, psycopg2.Error) as error :
print ("Error while connecting", error)
finally:
if(connection):
cursor.close()
connection.close()
You can follow this tutorial

Connect to MySql DB using mysql.connector

I am using mysql.connector to connect to a mysql DB, while i can connect manually to the db using sql server management, if i try connecting via code, it returns this error after awhile :
mysql.connector.errors.OperationalError: 2055: Lost connection to MySQL server at 'host:1234', system error: 10054 An existing connection was forcibly closed by the remote host
These are the connection details :
connection = mysql.connector.connect(host='host',
port = '1234',
database='DBname',
user='Usr',
password='pwd')
If I create a local mysql DB, the connection works just fine.
I assume some security stuff is going on, anyone else had encountered this situation ? Anything that I'm doing wrong? Should I add anything to the connection.connect input ?
Full code for reference :
import mysql.connector
from mysql.connector import Error
connection = mysql.connector.connect(host='host',
port = '1234',
database='DBname',
user='Usr',
password='pwd')
sql_select_Query = "select * from TableName"
cursor = connection.cursor()
cursor.execute(sql_select_Query)
records = cursor.fetchall()
print("Total numb of rows selected is : ", cursor.rowcount)
print("\nPrinting each row")
for row in records:
print(row)
connection.close()

Pymysql Windows Authentication Error

I am attempting to connect to SQL Server Management Studio. My code is below and returns the error: "init() got an unexpected keyword argument 'trusted'." I am using pymysql, would like to connect using Windows Authentication, and am running on 64 bit windows machine. Any help would be appreciated.
Edit - removed trusted. Error I am now receiving is 'No connection could be made because the target machine actively refused it'
import pymysql
import pymysql.cursors
conn = pymysql.connect(host = 'DESKTOP-6CIMC97')

Have you checked out the example on GitHub? trusted doesn't seem to be required.
https://github.com/PyMySQL/PyMySQL/blob/master/example.py
#!/usr/bin/env python
from __future__ import print_function
import pymysql
conn = pymysql.connect(host='localhost', port=3306, user='root', passwd='', db='mysql')
cur = conn.cursor()
cur.execute("SELECT Host,User FROM user")
print(cur.description)
print()
for row in cur:
print(row)
cur.close()
conn.close()

Pymysql Insert Into not working

I'm running this from PyDev in Eclipse...
import pymysql
conn = pymysql.connect(host='localhost', port=3306, user='userid', passwd='password', db='fan')
cur = conn.cursor()
print "writing to db"
cur.execute("INSERT INTO cbs_transactions(leagueID) VALUES ('test val')")
print "wrote to db"
The result is, at the top of the Console it says C:...test.py, and in the Console:
writing to db
wrote to db
So it's not terminating until after the execute command. But when I look in the table in MySQL it's empty. A record did not get inserted.
First off, why isn't it writing the record. Second, how can I see a log or error to see what happened. Usually there should be some kind of error in red if the code fails.

Did you commit it? conn.commit()

PyMySQL disable autocommit by default, you can add autocommit=True to connect():
conn = pymysql.connect(
host='localhost',
user='user',
passwd='passwd',
db='db',
autocommit=True
)
or call conn.commit() after insert

You can either do
conn.commit() before calling close
or
enable autocommit via conn.autocommit(True) right after creating the connection object.
Both ways have been suggested from various people at a duplication of the question that can be found here: Database does not update automatically with MySQL and Python