mac: mysql-connector-python connection issues on localhost - python

I am trying to walk through some basic tutorials to refresh myself with using MySQL with python3, and am hitting a snag immediately:
import mysql.connector
host='localhost'
user='root'
passwd='pwd'
mydb=mysql.connector.connect(host=host, user=user, password=passwd)
Running this, I get the error mysql.connector.errors.InterfaceError: 2003: Can't connect to MySQL server on 'localhost:3306' (61 Connection refused)
I can't find information on what I need to do outside of python to get this to work, it's not clear what authentication it's referring to. My unix username and password? I certainly don't want to store the latter in plaintext. I could enter it in manually (rather not). Is there a minimal set of instructions to get to the point where I can set up a cursor? Is there a way to set this up without a username and password? Any setup outside of my python environment I need to do, like in ipconfig/ifconfig?

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Timeout error while trying to connect to a remote Oracle Database in Python using cx_Oracle within a virtual environment

So I'm trying to establish a connection to a remote Oracle Database in python, from a Linux CentOS machine, but I'm getting the error-
cx_Oracle.DatabaseError: ORA-12170: TNS:Connect timeout occurred.
I'm using a virtual environment to run my code, wherein I have installed the cx-Oracle==8.3.0.
My python version is 3.6.2 and below is my code
import cx_Oracle
username ="username"
password ="password"
tns_dsn = cx_Oracle.makedsn("examplehost.com", 1528, "SID")
connection = cx_Oracle.connect(
username,
password,
tns_dsn)
print(connection.version)
I've also tried
connection = cx_Oracle.connect("username/password#examplehost.com:1528/SID") and possibly many other ways of connecting to the database, all have given me the same error.
I read other similar questions, some said to modify tnsnames.ora which I can't find anywhere on the system, as I'm using a virtual to implement this.
Please let me know where I'm going wrong or if I'm missing something.
Thanks

Using existing MySQL connection in PyCharm in python project without connecting manually again

I created a connection to a remote, tunneled MySQL server over the PyCharm GUI in the "Database" menu.
I'm trying to use this connection in the code itself, without connecting manually again to the SQL server and tunelling over SSH in the code.
Is this possible? I couldn't find anything relevant on the internet yet.
Thanks!

"OperationalError : no password supplied", when linking python and sql [duplicate]

This is probably a silly error but I cannot seem to find a satisfying solution.
When running db.create_all(), I got the following error.
sqlalchemy.exc.OperationalError: (OperationalError) fe_sendauth: no password supplied None None
My database link is set as
'postgresql://localhost/db_name'
This worked fine on my Mac and Heroku, but is not OK on ubuntu (digitalocean).
Any ideas what I might be doing wrong?
You probably just need to remove "localhost" from your connection string:
'postgresql:///db_name'
That tells psycopg2 to use Unix-domain sockets. Your default configuration will use "ident" so you'll be connecting as the user that runs the script. In the default configuration, "md5" only applies to TCP connections.
URL pattern should be:
postgresql://user:password#localhost:5432/database_name
pip install psycopg2
the user should be postgres or any other user you have created and intend to use
similarly for mySql it would be:
mysql://user:pass#localhost:3306/database_name
pip install mysql-python
On your Mac, PostgreSQL was set up for trust or peer authentication for connections from localhost.
On your Ubuntu box it's set up for md5 authentication for connections from localhost.
You'll want to configure a password, or change the authentication mode. See pg_hba.conf, and the Ubuntu guide for PostgreSQL (there's a section about this error).
Below worked for me. Your connection to your postgres database requires a password; thus, below is what you should write..
pg_user = "magicmike"
pg_pwd = "test123"
pg_port = "5432"
app.config["SQLALCHEMY_DATABASE_URI"] = "postgresql://{username}:{password}#localhost:{port}/foodversity_db".format(username=pg_user, password=pg_pwd, port=pg_port)
First make sure that the database server is connected and then run the command again.Silly, but it worked for me.
For Remote Server
remote server => postgresql://<username>:<password>#<ipaddress>:<port>/<database>
For Local in configuration use
local db => postgressql:///<database>

Cannot connect mysql through python

I did a python -m pip install mysql-connector and able to successfully run import mysql.connector through python. But when I am trying to run the below code.
import mysql.connector
mydb = mysql.connector.connect(
host="localhost",
user="yourusername",
passwd="yourpassword"
)
print(mydb)
It is failing with InterfaceError: 2003: Can't connect to MySQL server on 'localhost:3306' (10061 No connection could be made because the target machine actively refused it)
Since I did pip install for mysql.connector I am not sure of user and passwd.
I connected my database instance from Amazon RDS to mySql workbench, created a python file that looks like his and got the exact error. Everyone says you could have a system firewall problem but nothing straight forward.
The connector is just a means of communicating with a mysql database programically.
You need this, or access to a mysql server to use the connector.
https://dev.mysql.com/downloads/mysql/
The host is obviously localhost when you want to access it locally on your machine. This only works if the server is running on your machine. You can connect a remote server by changing the host to a valid IP address and providing valid credentials. If you use it remotely make sure the server has access through the firewall and that you properly forward the TCP port you decide to use. You may not have to forward, but I would as a general rule of thumb to make it one less thing to check when troubleshooting.
Good luck

Python and Connecting to MySQL over SSH

I am trying to connect to a MySQL database on someone else's "machine". When I use Navicat for MySQL, I have no problem connecting to it. I am trying to do the same with Python so that I do not have to use the GUI interface. I know all my info below is correct (even though I swap fake info) -- can anyone spot where I went wrong? The error I get is OperationalError: (2005, "Unknown MySQL server host 'FTP_hostname' (0)")
My code (using paramiko for the SSH):
import MySQLdb
import paramiko
import time
ssh = paramiko.SSHClient()
ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy())
ssh.connect('SSH_hostname', 22, username='me', password='pswrd')
time.sleep(1)
db = MySQLdb.connect(host="FTP_hostname",
user="root",
passwd="pswrd2",
db="MyDB")
cur = db.cursor()
Again, I put all this into Navicat and connect no problem. Hoping you can help! Thanks!
MySQL, like most databases, by default runs locally and disallows access from outside networks. As such, you cannot connect to it from an external computer.
Navicat, being a software explicitely for remote administration of databases, likely connects via SSH and tunnels the MySQL connection over it. That way it can act as if the database was installed locally, and for the database it looks as if it was accessed locally.
You could try to do the same by creating a tunnel using Paramiko; see also this question.
If you still in need of connecting to a remote MySQL db via SSH I have used a library named sshtunnel, that wraps ands simplifies the use of paramiko (a dependency of the sshtunnel).
You can check my answer in another similar question with some sample code to use it.
db = MySQLdb.connect(host="FTP_hostname",
Would the host not need to be 127.0.0.1 (localhost) as the tunnel is making the MySQL DB local to the machine that the python script is running on?

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