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Oracle Connection in Python Using create_engine

I am trying to connect to an oracle database in Python using create_engine. This database does not have a username or password.
I see this is the format now:
oracle_db = sqlalchemy.create_engine('oracle://user:pass#server').
However, if this connection has NO username or password, how would the connection string look? I've tried DMIT_connection = create_engine('oracle+cx_oracle://#....) with no luck. When I go to write a pandas df to the database using to_sql I get the error below because I cannot get the connection right give that there is no username or password.
The error occurs because this database has no username (picked up from the localhost machine) and there is no password.
The error I get is this: DatabaseError: (cx_Oracle.DatabaseError) ORA-12545: Connect failed because target host or object does not exist (Background on this error at: http://sqlalche.me/e/14/4xp6)

Let me know authentication type used. If its external authentication , picking credentials from wallet, you can try sample code mentioned here
How to use SqlAlchemy to connect Database similar to cx_oracle when we use external authorization like wallets with TNS(net service name)

How do I connect Python to my Postgres Server?

I have been having major trouble connecting my python shell to my postgres. I am doing this on windows. I have downloaded psycopg2 and everything for this to process, however it still is not working.
import psycopg2
conn=psycopg2.connect("dbname = 'test' user ='postgres' host ='localhost' password = 'mypassword'")
It gives me an error telling me that the database "test" does not exist, however it does! If you guys have any advice at all on what I should test out, that would be amazing. Thank you!

You can layout connection parameters as a string and pass it to the connect() function as like:
conn = psycopg2.connect("dbname=test user=postgres password=postgres")
Or you can use a list of keyword arguments like
conn = psycopg2.connect(host="localhost",database="test", user="postgres", password="postgres")
If its still fails then you should check on PostgreSQL side. You should try to connect the db in question using command line and see if error re appears or not. if it appears then something is missing on DB server side.

python-mysql cursor.execute failing with access denied error

I have two machines: local_machine, server_machine. I have mysql server on server_machine and sftp server on local_machine. I am trying to send sritest.csv file (UTF-8) from local_machine to server_machine using python. These are the contents of sritest.csv:
1,2,3
I have the sql query saved in sritest.sql and these are the contents of the file:
LOAD DATA INFILE '{}'
INTO TABLE TESTBED_STAGING.test
COLUMNS TERMINATED BY ','
;
This is the python script I have now:
import MySQLdb
import os
import string
# Open database connection
db = MySQLdb.connect (host="1.2.3.4",port=3306,user="app_1",\
passwd="passwd",db="TESTBED_STAGING")
cursor=db.cursor()
#Query under testing
sql = open('sritest.sql','r').read()
print sql
l = os.listdir(".")
for file_name in l:
if file_name.endswith('sritest.csv'):
print 'the csv file we are reading is: '+file_name
#try:
cursor = db.cursor()
print 'filename is '+sql.format(file_name)
cursor.execute(sql.format(file_name))
db.commit()
'''
except Exception:
# Rollback in case there is any error
db.rollback()
print 'ERROR - So, rollback :( :( '
'''
# disconnect from server
db.close()
In the above script, I commented try,except so I can see the error where it breaks. Currently the code is breaking at cursor.execute(sql.format(file_name)) line with this error:
OperationalError: (1045, "Access denied for user 'app_1'#'%' (using password: YES)")
I have been playing around but not able to fix it. Any suggestions/ideas?

For starters, creating cursor at every loop is not a good idea. You've already created a cursor earlier, so you can remove the cursor declaration in the for loop.
Second, I think your error is due to lack of access on MySQL server at 1.2.3.4 remotely using user app_1. Try this on the server's MySQL console,
GRANT ALL PRIVILEGES ON TESTBED_STAGING.* TO 'app_1'#'%';
Lastly, try and avoid using print "line" notation and start switching to the print("line") notation for compatibility with Python 3.x

I figured out the answer and decided to leave this question open for those who might face the similar problem:
In the MySQL server (server_machine), make sure you do this after you start mysql:
mysql>grant all privileges on *.* to 'app_1'#'%' identified by 'passwd';
change LOAD DATA INFILE '{}' in sritest.sql to LOAD DATA LOCAL INFILE '{}'
In the python code, edit the MySQLdb.connect statement as:
db = MySQLdb.connect (host="1.2.3.4",port=3306,user="app_1",\
passwd="passwd",db="TESTBED_STAGING", local_infile=1)
All errors are eliminated and data is transferred.

SQL server bulkinsert errors

When I run this query to bulkinsert a file on a shared drive to SQL server 2008 with username and password (not Windows authentication), I get these errors. DBA, system admins and network guys are all denying these errors are related to their teams and I am lost... Can anyone please help me to identify where the issue is? When I run bulkinsert with database username and password, what authentication does SQL server use to open the file?
Run this on MS Management Studio
BULK INSERT DatabaseName.dbo.TableName
FROM '\\shared_server\parent\child\file_name.txt'
WITH(FIRE_TRIGGERS, DATAFILETYPE='char', FIELDTERMINATOR='\t',ROWTERMINATOR='\n', FIRSTROW=2);
and I get
Cannot bulk load because the file "\\shared_server\parent\child\file_name.txt" could not be opened. Operating system error code 5(Access is denied.).
Run this on python
import pyodbc
database = 'DatabaseName'
username = 'username'
password = 'password'
server = 'server_name'
failover = 'failover_server_name'
cnxn_string = 'DRIVER={SQL Server Native Client 10.0};SERVER=%s;FAILOVER_PARTNER=%s;DATABASE=%s;UID=%s;PWD=%s;CHARSET=UTF8' % (server, failover, database, username, password)
cnxn = pyodbc.connect(cnxn_string)
cursor = cnxn.cursor()
query = r"""
BULK INSERT Estimates.dbo.FundamentalsIS
FROM '\\shared_server\parent\child\file_name.txt'
WITH(FIRE_TRIGGERS, DATAFILETYPE='char', FIELDTERMINATOR='\t',ROWTERMINATOR='\n', FIRSTROW=2);
"""
cursor.execute(query)
cursor.commit()"
and I get
ProgrammingError: ('42000', '[42000] [Microsoft][SQL Server Native Client 10.0][SQL Server]Cannot bulk load because the file "\\shared_server\parent\child\file_name.txt" could not be opened. Operating system error code 1326(Logon failure: unknown user name or bad password.). (4861) (SQLExecDirectW)')

Could the MS SQL server 2008 possibly be on a different security group (or have different settings) than the shared drives, where the file is located?
Because the bulk insert operation is run on the MS Management studio server side, it might not have access to the file, the 'access denied' leads me to believe DB server cannot get to shared file drive, and possibly does not have permission to access it. Likewise, even if using python to execute the BULK INSERT statement, the DB server still needs to have access to where ever the file is located.
I had a similar issue in the past, because the DB server could not get to the shared file, located elsewhere. My workaround was to use local computer to read in the file and run the insert queries using python. It sounds like the local environment has access to both and can be used as the central communication hub. You might have to do something similar to
https://stackoverflow.com/a/6482610/3761363
https://stackoverflow.com/a/11219626/3761363

Python connecting to MySQL database name error

I got the following code from this site to connect to a mysql database through python (which is much appreciated by the way). I have used it once already to connect to a database on the server, but in a different file. However I know want to connect to another database on the same server but i keep getting error message to do with the database name.
I am using exactly the same code as I was before to connect, however i have only changed the database name to the other one i want to connect to. I can look at the database through puTTY, and see that it is called the correct name and that all the data is there, but just cant seem to connect properly through the Python.
Thanks in advance for any help!
#!/usr/bin/python
import MySQLdb
db = MySQLdb.connect(host="127.0.0.1", # your host, usually localhost
user="root", # your username
passwd="........", # your password
db="opt_out") # name of the data base
# you must create a Cursor object. It will let
# you execute all the query you need
cur = db.cursor()
# Use all the SQL you like
cur.execute("SELECT * FROM opted_in")
# print all the first cell of all the rows
for row in cur.fetchall() :
print row[0]
And this is the error code i get in return when i try and execute the python file through puTTY:
Traceback (most recent call last):
File "/var/www/html/vra/ConnectAdiDB.py", line 7, in <module>
db="opt_out") # name of the data base
File "/usr/lib64/python2.6/site-packages/MySQLdb/__init__.py", line 81, in Connect
return Connection(*args, **kwargs)
File "/usr/lib64/python2.6/site-packages/MySQLdb/connections.py", line 187, in __init__
super(Connection, self).__init__(*args, **kwargs2)
_mysql_exceptions.OperationalError: (1045, "Access denied for user 'root'#'localhost' (using password: YES)")

The Password must be wrong (I Think so)
So Try to reset the password so:
first off turn of the mysql Service like so
Ubuntu/Debian:
sudo service mysql stop
After That Do So:
sudo service mysql start
When Done Start mysql like so:
sudo mysql
An execute:
UPDATE mysql.user SET Password=PASSWORD('NEW-PASSWORD') WHERE User='root';
FLUSH PRIVILEGES;