What's causing 'unable to connect to data source' for pyodbc?

Question

I\'m trying to connect to an MSSQL database from python on Linux (SLES).

I have installed pyodbc and Free TDS. From the command line:

tsql -H server          


        

Answer 1

I found my way here after an Ubuntu 18.04 upgrade broke my pyodbc connections. Turns out, in my //etc/odbcinst.ini file my driver description order was switched around.

So when I called:

from pyodbc import connect,drivers
conn = connect(driver=drivers()[0], ...

I should have been calling:

conn = connect(driver=drivers()[1], ...  

In other words, I was calling the wrong driver because of a simple index issue. Hope this helps someone else.

Answer 2

The follow worked for me:

Modify python2.7/site-packages/sql_server/pyodbc/base.py

def get_new_connection(self, conn_params):
...
-    cstr_parts['SERVERNAME'] = host
+    cstr_parts['SERVER'] = host
+    cstr_parts['PORT'] = str(port)

Answer 3

I try with:

• MS SQL 2008 Datacenter
• Ubuntu 12.04 TLS (amd64)
• Python 2.7

And this works for me:

Test connection:

tsql -H 10.19.4.42 -p 1433 -U DAVIDG -P 123456

on /etc/odbcinst.ini add:

[ODBC]
Trace = Yes
TraceFile = /tmp/odbc.log

[FreeTDS]
Description = TDS driver (Sybase/MS SQL)
Driver = /usr/lib/x86_64-linux-gnu/odbc/libtdsodbc.so
Setup =  /usr/lib/x86_64-linux-gnu/odbc/libtdsS.so
UsageCount = 1

on /etc/odbc.ini add:

[SQLDemo]
Description=my dsn
Driver=FreeTDS
Database=teste3
Servername=SQLDemo

on /etc/freetds/freetds.conf add:

[SQLDemo]
        host = 10.19.4.42
        port = 1433
        tds version = 8.0

test with test.py:

#!/usr/bin/python

import pyodbc
cnx = pyodbc.connect("DSN=SQLDemo;UID=DAVIDG;PWD=123456")

cursor = cnx.cursor()
cursor.execute("select * from Company;")
for row in cursor:
  print row.Name

Answer 4

In my case my host files are missing when i ping to that server it was not pinging. Then i noticed my host files are missing by applying sudo vi /etc/hosts command in the terminal. I added my host and ip address and worked fine for me.

Answer 5

I was also having problems with this after upgrading my version of ubuntu to 12.04. My old freetds config /etc/freetds/freetds.conf was no being found so I had to move it to /usr/local/etc at which point it started working again.

Also my driver location is /usr/local/lib/libtdsodbc.so

Hope this helps save someone a day and a half!

Answer 6

You can also set an environmental variable in your python script:

os.environ['TDSVER'] = '8.0'