How to connect to SQL Server using FreeTDS ODBC

1
votes

I am trying to connect to my company's SQL Server Databases via my MacBook and have followed the steps outlined here: https://github.com/mkleehammer/pyodbc/wiki/Connecting-to-SQL-Server-from-Mac-OSX but keep getting the following error when I get to the following step:

Check that all is OK by running isql TEST myuser mypassword. You should see the following:

+---------------------------------------+
| Connected!                            |
|                                       |
| sql-statement                         |
| help [tablename]                      |
| quit                                  |
|                                       |
+---------------------------------------+

I already verified that the following works:

Test the connection using the tsql utility, e.g. tsql -S TEST -U myuser -P mypassword. If this works, you should see the following:

locale is "en_US.UTF-8"
locale charset is "UTF-8"
using default charset "UTF-8"
1>

The odbcinst.ini and odbc.ini configuration files are both in the same directory.

MacBook-Pro: myname$ odbcinst -j
unixODBC 2.3.7
DRIVERS............: /etc/odbcinst.ini
SYSTEM DATA SOURCES: /etc/odbc.ini
FILE DATA SOURCES..: /etc/ODBCDataSources
USER DATA SOURCES..: /Users/myname/.odbc.ini
SQLULEN Size.......: 8
SQLLEN Size........: 8
SQLSETPOSIROW Size.: 8

odbcinst.ini file config:

[FreeTDS]
Description=FreeTDS Driver for Linux & MSSQL
Driver=/usr/local/lib/libtdsodbc.so
Setup=/usr/local/lib/libtdsodbc.so
UsageCount=1

odbc.ini config:

[TEST]
Description         = Test to SQLServer
Driver              = FreeTDS
Servername          = ServerName

freetdf.conf 

#   $Id: freetds.conf,v 1.12 2007-12-25 06:02:36 jklowden Exp $
#
# This file is installed by FreeTDS if no file by the same 
# name is found in the installation directory.  
#
# For information about the layout of this file and its settings, 
# see the freetds.conf manpage "man freetds.conf".  

# Global settings are overridden by those in a database
# server specific section
[global]
        # TDS protocol version
    tds version = auto

    # Whether to write a TDSDUMP file for diagnostic purposes
    # (setting this to /tmp is insecure on a multi-user system)
;   dump file = /tmp/freetds.log
;   debug flags = 0xffff

    # Command and connection timeouts
;   timeout = 10
;   connect timeout = 10

    # If you get out-of-memory errors, it may mean that your client
    # is trying to allocate a huge buffer for a TEXT field.  
    # Try setting 'text size' to a more reasonable limit 
    text size = 64512

    # If you experience TLS handshake errors and are using openssl,
    # try adjusting the cipher list (don't surround in double or single quotes)
    # openssl ciphers = HIGH:!SSLv2:!aNULL:-DH

# A typical Sybase server
[egServer50]
    host = symachine.domain.com
    port = 5000
    tds version = 5.0

# A typical Microsoft server
[TEST]
    host = ServerName
    port = 1433
    tds version = 7.3
    client charset = UTF-8

My command and the output: isql TEST myuser mypass -v [IM002][unixODBC][Driver Manager]Data source name not found and no default driver specified [ISQL]ERROR: Could not SQLConnect

2
pythonsql-serverpyodbcfreetdsunixodbc
Are you telling us that tsql -S MYMSSQL ... works for you? If so, then you're not giving us the whole story because nowhere in any of your configuration files is there an entry named MYMSSQL. Please edit your question to describe exactly (and concisely) what you are really doing, what works, and what doesn't. - Gord Thompson
Also, the tds version = 8.0 isn't invalid. This won't prevent the connection, but you should choose a proper tds version, depending on your version of FreeTDS. See the second table on this page: freetds.org/userguide/choosingtdsprotocol.htm - FlipperPA
@GordThompson I updated the question - not sure how that changes anything as you could have inferred from my configuration files that I was using TEST in the commands instead of MYMSSQL. - dir101
@FlipperPA I updated it to the correct version, 7.3, but still no luck - dir101
@dir101 Yeah, that wouldn't fix this problem but it will save you headaches down the road. :) - FlipperPA

2 Answers

5
votes

Start by confirming that you're editing the correct configuration files.

You can confirm FreeTDS's view of the world with:

$ tsql -C
Compile-time settings (established with the "configure" script)
                            Version: freetds v1.1.11
             freetds.conf directory: /usr/local/etc
     MS db-lib source compatibility: no
        Sybase binary compatibility: yes
                      Thread safety: yes
                      iconv library: yes
                        TDS version: 7.3
                              iODBC: no
                           unixodbc: yes
              SSPI "trusted" logins: no
                           Kerberos: yes
                            OpenSSL: yes
                             GnuTLS: no
                               MARS: yes

This shows that the System-wide freetds.conf file will be at the path /usr/local/etc/freetds.conf, although you can have your own user-specific version at ~/.freetds.conf.

If you're trying to connect to an SQL Server on your network, fred.example.com, you can create an alias for it in freetds.conf:

[fred]
    host = fred.example.com
    port = 1433
    tds version = auto
    client charset = UTF-8

The [fred] alias is not case-sensitive. TSQL can connect to it with any of the following:

$ tsql -S fred -U "FRED\YourSQLUserName" -P "YourSQLPassword"
$ tsql -S FRED -U "FRED\YourSQLUserName" -P "YourSQLPassword"
$ tsql -S FrEd -U "FRED\YourSQLUserName" -P "YourSQLPassword"

... and so on.

Once you've established that FreeTDS is working you can move on to ODBC. You can check ODBC's view of the world with:

$ odbcinst -j
unixODBC 2.3.7
DRIVERS............: /usr/local/etc/odbcinst.ini
SYSTEM DATA SOURCES: /usr/local/etc/odbc.ini
FILE DATA SOURCES..: /usr/local/etc/ODBCDataSources
USER DATA SOURCES..: /Users/YourUserName/.odbc.ini
SQLULEN Size.......: 8
SQLLEN Size........: 8
SQLSETPOSIROW Size.: 8

Start by editing the /usr/local/etc/odbcinst.ini file (which start out empty) and adding the following:

[FreeTDS]
Description=FreeTDS Driver for Linux & MSSQL
Driver=/usr/local/lib/libtdsodbc.so
Setup=/usr/local/lib/libtdsodbc.so
UsageCount=1

Next, you can add a System-wide data source for Fred in /usr/local/etc/odbc.ini or a user-specific one in ~/.odbc.ini:

[fred]
Description         = Test to SQLServer
Driver              = FreeTDS
Servername          = fred

Note that the Servername = fred here points to the [fred] in freetds.conf. It's not case-sensitive, either, but you shouldn't have one called fred and the other called daphne.

Now you should be able to connect using ODBC with:

$ isql fred "FRED\YourSQLUserName" "YourSQLPassword"

Hope this helps.

2
votes

Part of your confusion is likely due to your naming everything "TEST". This works for me:

freetds.conf

[MYMSSQL_SERVER]
    host = 192.168.0.179
    port = 49242
    tds version = 7.0

odbcinst.ini

[FreeTDS]
Description=FreeTDS ODBC
Driver=/usr/lib/x86_64-linux-gnu/odbc/libtdsodbc.so

odbc.ini

[TEST]
Description         = Test to SQLServer
Driver              = FreeTDS
Servername          = MYMSSQL_SERVER

isql needs the DSN name

gord@xubu-Inspiron-1720:~$ isql TEST sa sapassword
+---------------------------------------+
| Connected!                            |
|                                       |
| sql-statement                         |
| help [tablename]                      |
| quit                                  |
|                                       |
+---------------------------------------+
SQL> SELECT @@SERVERNAME
+---------------------------------------------------------------------------------------------------------------------------------+
|                                                                                                                                 |
+---------------------------------------------------------------------------------------------------------------------------------+
| GORD-HP\SQLEXPRESS                                                                                                              |
+---------------------------------------------------------------------------------------------------------------------------------+
SQLRowCount returns 1
1 rows fetched

tsql needs the FreeTDS server name

gord@xubu-Inspiron-1720:~$ tsql -S MYMSSQL_SERVER -U sa -P sapassword
locale is "en_CA.UTF-8"
locale charset is "UTF-8"
using default charset "UTF-8"
1> SELECT @@SERVERNAME
2> GO

GORD-HP\SQLEXPRESS
(1 row affected)

Note that if you are only using ODBC then you don't need an entry in freetds.conf. The trick is to have the DSN use Server instead of Servername. This works, too:

odbc.ini

[TEST_ODBC_ONLY]
DRIVER=FreeTDS
SERVER=192.168.0.179
PORT=49242
TDS_Version=7.0

which isql likes just fine:

gord@xubu-Inspiron-1720:~$ isql TEST_ODBC_ONLY sa sapassword
+---------------------------------------+
| Connected!                            |
|                                       |
| sql-statement                         |
| help [tablename]                      |
| quit                                  |
|                                       |
+---------------------------------------+
SQL> SELECT @@SERVERNAME
+---------------------------------------------------------------------------------------------------------------------------------+
|                                                                                                                                 |
+---------------------------------------------------------------------------------------------------------------------------------+
| GORD-HP\SQLEXPRESS                                                                                                              |
+---------------------------------------------------------------------------------------------------------------------------------+
SQLRowCount returns 1
1 rows fetched

And, by extension, with pyodbc you don't even need a DSN if you use a DSN-less connection:

connection_string = (
    'DRIVER=FreeTDS;'
    'SERVER=192.168.0.179;'
    'PORT=49242;'
    'TDS_Version=7.0;'
    'UID=sa;PWD=sapassword;'
)
cnxn = pyodbc.connect(connection_string)
crsr = cnxn.cursor()
print(crsr.execute("SELECT @@SERVERNAME").fetchval())
# GORD-HP\SQLEXPRESS