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Connecting Python to SQL Server

I work for a nonprofit and I am trying to establish a connection from python scripts to our sql server (Microsoft SQL Server Management Studio 18) as a proof of thought and I am running into an error found below. I cannot find a solution and I have searched across StackOverflow and have tried different arrangements of codes to no success. Underneath the error is my code to connect to sql using pyodbc. I have been successful establishing a remote connection to sql on R (RODBC package) but trying to move to python. Is this a security issue on the SQL server side or am I missing a syntax? For security purposes, I filled in the username and password with fill-ins. Any help would be great!
('HY000', '[HY000] [Microsoft][ODBC Driver 17 for SQL Server][SQL Server]Cannot open server "foodbankcenc.org" requested by the login. The login failed. (40532) (SQLDriverConnect); [HY000] [Microsoft][ODBC Driver 17 for SQL Server][SQL Server]Cannot open server "foodbankcenc.org" requested by the login. The login failed. (40532)')
import pyodbc
conn = pyodbc.connect(Driver='{ODBC Driver 17 for SQL Server}',
Server= 'fbnc.database.windows.net',
Database= 'FBData',
user ='user',
password= 'password')
cursor = conn.cursor()
cursor.execute('SELECT * FROM table_name')
for i in cursor:
print(i)

My df.to_sql is saying can't establish a connection to SQL Server. This is a local instance with no login creds

I ran several df.to_sql scripts about 1 year ago, and everything worked perfectly fine, but now I'm getting an error that says the following:
OperationalError: ('08001', '[08001] [Microsoft][SQL Server Native Client 11.0]Named Pipes Provider: Could not open a connection to SQL Server [2]. (2) (SQLDriverConnect); [08001] [Microsoft][SQL Server Native Client 11.0]Login timeout expired (0); [08001] [Microsoft][SQL Server Native Client 11.0]A network-related or instance-specific error has occurred while establishing a connection to SQL Server. Server is not found or not accessible. Check if instance name is correct and if SQL Server is configured to allow remote connections. For more information see SQL Server Books Online. (2)')
Here are two sample scripts that I am testing.
import sqlalchemy
import pyodbc
engine = pyodbc.connect(driver='{SQL Server Native Client 11.0}', host='CEDUMII6', database='TestDB', trusted_connection='yes')
df.to_sql('healthcare', engine, if_exists='replace', index=True, chunksize=100000)
and
import sqlalchemy
import pyodbc
engine = "mssql+pyodbc://CEDUMII6/TestDB?driver=SQL Server Native Client 11.0?trusted_connection=yes"
df.to_sql('healthcare', con=engine, if_exists='replace', index=True, chunksize=100000)
and
import sqlalchemy
import pyodbc
server = 'CEDUMII6'
database = 'TestDB'
con = pyodbc.connect('DRIVER={ODBC Driver 11 for SQL Server};SERVER=' + server + ';DATABASE=' + database +';Trusted_Connection=yes')
df.to_sql('healthcare', con=engine, if_exists='append', index=True, chunksize=100000)
My firewall is off! I must be missing something simple, but I can't tell what it is. Any idea what's wrong here?

This is what ultimately worked for me.
import pyodbc
engine = "mssql+pyodbc://LAPTOP-CEDUMII6\SQLEXPRESS01/Test_DB?driver=SQL Server Native Client 11.0?trusted_connection=yes"
all_data.to_sql('health', engine, if_exists='replace', index=True)

Logon failed (pyodbc.InterfaceError) ('28000', "[28000] [Microsoft][ODBC SQL Server Driver][SQL Server]Login failed for user 'xxxx'

I have big issues to connect to the sql sever with python 3.8. I wonder if I need to downgrade to 3.7 python and if there is something else I am doing wrong?
HERE IS MY CODE AND ERROR MESSAGE:
params = urllib.parse.quote_plus \
('Driver={SQL
Server};Server=tcp:xxxxx.database.windows.net,1433;
Database=GroceryDB;Uid=xxxxx;Pwd=
{xxxx};Encrypt=no;Connection Timeout=30;')
conn_str = 'mssql+pyodbc:///?odbc_connect={}'.format(params)
engine =
sqlalchemy.engine.create_engine(conn_str,echo=False,pool_pre_
ping=True)
Logon failed (pyodbc.InterfaceError) ('28000', "[28000] [Microsoft][ODBC SQL Server Driver][SQL Server]Login failed for user 'xxxx'.

NEWEST
You can follow the document(Open the ODBC Data Source Administrator) to check the odbc driver whether installed successfully.
PRIVIOUS
Below code works for me.
from urllib import parse
import pyodbc
from sqlalchemy import create_engine
import urllib
params = parse.quote_plus \
(r'Driver={ODBC Driver 17 for SQL Server};Server=tcp:yoursqlserver.database.windows.net,1433;Database=dbname;Uid=sasasa;Pwd={pwd};Encrypt=yes;TrustServerCertificate=no;Connection Timeout=30;')
conn_str="mssql+pyodbc:///?odbc_connect={}".format(params)
engine= create_engine (conn_str,echo=True)
connection = engine.connect()
result = connection.execute("select 1+1 as res")
for row in result:
print("res:", row['res'])
connection.close()

pyodbc- connection failure to SQL Server

I have been trying to connect to Microsoft SQL Server. I have an ODBC connection set up and the test is successful. I am not using Windows Authentication to connect to SQL Server but it keep getting this error:
Cannot be used with Windows authentication
InterfaceError: ('28000', '[28000] [Microsoft][ODBC SQL Server Driver][SQL Server]Login failed. The login is from an untrusted domain and cannot be used with Windows authentication. (18452) (SQLDriverConnect); [28000] [Microsoft][ODBC SQL Server Driver]Invalid connection string attribute (0); [28000] [Microsoft][ODBC SQL Server Driver][SQL Server]Login failed. The login is from an untrusted domain and cannot be used with Windows authentication. (18452); [28000] [Microsoft][ODBC SQL Server Driver]Invalid connection string attribute (0)')
Here is my code:
import pyodbc
cnxn = pyodbc.connect(Driver='{SQL Server}',
Server='servername.abc.xyz.co.com',
username = 'user_xyz',
password = 'abcdfgh')
I am using Windows 7. Please help me debug this problem
Thanks

I was able to solve this by defining the dsn connection as below:
dsn="DRIVER={SQL
SERVER};server=ip_address_here;database=db_name_here;uid=user;pwd=password"
This worked and I was able to connect and query the sql server.

This is how I do it and it works:
import pyodbc
server_name = "server_name"
db_name = "db_name"
server = "Server="+str(server_name)
db = "Database="+str(db_name)
key = "Driver={SQL Server Native Client 11.0};"+server+";"+db+";"+"Trusted_Connection=yes;"
cnxn = pyodbc.connect(key)

Cannot establish connection to sql-server using pyodbc on Windows 7

I'm using ActivePython 2.7.2.5 on Windows 7.
While trying to connect to a sql-server database with the pyodbc module using the below code, I receive the subsequent Traceback. Any ideas on what I'm doing wrong?
CODE:
import pyodbc
driver = 'SQL Server'
server = '**server-name**'
db1 = 'CorpApps'
tcon = 'yes'
uname = 'jnichol3'
pword = '**my-password**'
cnxn = pyodbc.connect('DRIVER={SQL Server};SERVER=server;DATABASE=db1;UID=uname;PWD=pword;Trusted_Connection=yes')
cursor = cnxn.cursor()
cursor.execute("select * from appaudit_q32013")
rows = cursor.fetchall()
for row in rows:
print row
TRACEBACK:
Traceback (most recent call last):
File "pyodbc_test.py", line 9, in <module>
cnxn = pyodbc.connect('DRIVER={SQL Server};SERVER=server;DATABASE=db1;UID=uname;PWD=pword;Trusted_Connection=yes')
pyodbc.Error: ('08001', '[08001] [Microsoft][ODBC SQL Server Driver][DBNETLIB]SQL Server does not exist or access denied. (17) (SQLDriverConnect); [01000] [Microsoft][ODBC SQL Server Driver][DBNETLIB]ConnectionOpen (Connect()). (53)')

You're using a connection string of 'DRIVER={SQL Server};SERVER=server;DATABASE=db1;UID=uname;PWD=pword;Trusted_Connection=yes', you're trying to connect to a server called server, a database called db1, etc. It doesn't use the variables you set before, they're not used.
It's possible to pass the connection string parameters as keyword arguments to the connect function, so you could use:
cnxn = pyodbc.connect(driver='{SQL Server}', host=server, database=db1,
trusted_connection=tcon, user=uname, password=pword)

I had the same error message and in my case the issue was the [SQL Server] drivers required TLS 1.0 which is disabled on my server. Changing to the newer version of the SNAC, SQL Server Native Client 11.0 fixed the problem.
So my connection string looks like:
cnxn = pyodbc.connect(driver='{SQL Server Native Client 11.0}',
host=server, database=db1, trusted_connection=tcon,
user=uname, password=pword)

I had faced this error due to another reason.
It was because my server had a "port" apart from the address.
I could fix that by assigning the following value to "Server" parameter of the connection string.
"...;Server=<server_name>,<port#>;..."
Note that it is a 'comma' and not 'colon'/'period'

cnxn = pyodbc.connect(driver='{SQL Server}', host=server, database=db1,
user=uname, password=pword)
print(cnxn)
I removed "Trusted_Connection" part and it worked for me.

Different security risks exist with either method. If you use Sql Server authentication you expose your userid/password in the code. But at least you process with the same credentials. If you use Windows authentication you have to insure all the possible users are setup with the right permission in the Sql server. With Sql authentication you can setup just one user but multiple people can use that one Sql User permissions wise.

I had the same issue today. I was using localhost in the connectionstring. Got rid of the issue by replacing localhost woth 'server name',. My db and application are running in the same machine.
If you don't have server name
go to Sql server management studio and execute below query, which will give you the server name.
SELECT ##SERVERNAME
The connection string look as below
conn = pyodbc.connect('Driver={SQL Server};'
'Server=myServerName;'
'Database=mydb;'
'Trusted_Connection=yes;')