Pyodbc - “Data source name not found, and no defau

问题:

I have trouble getting pyodbc work. I have unixodbc , unixodbc-dev, odbc-postgresql, pyodbc packages installed on my Linux Mint 14. I am losing hope to find solution on my own, any help appreciated. See details below:

Running:

>>> import pyodbc
>>> conn = pyodbc.connect("DRIVER={PostgreSQL};SERVER=localhost;DATABASE=test;USER=openerp;OPTION=3;")

Gives me:

>>> pyodbc.Error: ('IM002', '[IM002] [unixODBC][Driver Manager]Data source name not found, and no default driver specified (0) (SQLDriverConnect)')

# odbcinst -j gives:

unixODBC 2.2.14
DRIVERS............: /etc/odbcinst.ini
SYSTEM DATA SOURCES: /etc/odbc.ini
FILE DATA SOURCES..: /etc/ODBCDataSources
USER DATA SOURCES..: /home/atman/.odbc.ini
SQLULEN Size.......: 4
SQLLEN Size........: 4
SQLSETPOSIROW Size.: 2

Which makes me think there is a unixodbc configuration problem. Here are my unixodbc config file contents:

File /etc/odbcinst.ini:

[PostgreSQL ANSI]
Description     = PostgreSQL ODBC driver (ANSI version)
Driver      = psqlodbca.so
Setup       = libodbcpsqlS.so
Debug       = 0
CommLog     = 1
UsageCount      = 2

[PostgreSQL Unicode]
Description     = PostgreSQL ODBC driver (Unicode version)
Driver      = psqlodbcw.so
Setup       = libodbcpsqlS.so
Debug       = 0
CommLog     = 1
UsageCount      = 2

File /etc/odbc.ini :

[PostgreSQL test]
Description         = PostgreSQL 
Driver              = PostgreSQL ANSI
Trace               = No
TraceFile           = /tmp/psqlodbc.log
Database            = template1
Servername          = localhost
UserName            =
Password            =
Port                =
ReadOnly            = Yes
RowVersioning       = No
ShowSystemTables    = No
ShowOidColumn       = No
FakeOidIndex        = No
ConnSettings        =

File ~/.odbc.ini:

[DEFAULT]
Driver = PostgreSQL

[PostgreSQL]
Description         = Test to Postgres
Driver              = PostgreSQL
Trace               = Yes
TraceFile           = sql.log
Database            = nick
Servername          = localhost
UserName            =
Password            =
Port                = 5432
Protocol            = 6.4
ReadOnly            = No
RowVersioning       = No
ShowSystemTables    = No
ShowOidColumn       = No
FakeOidIndex        = No
ConnSettings        =

回答1:

I believe the answer to your problem is that in your ~/.odbc.ini file you are saying to use driver PostgreSQL - but you have not defined that driver in your /etc/odbcinst.ini file. Try changing PostgreSQL to PostgreSQL ANSI or PostgreSQL Unicode (both of which are defined in /etc/odbcinst.ini).

回答2:

For me, the issue was the actual location of my odbc.ini and odbcinst.ini files.

On many systems, the install location of these files is in /etc/

However, in my case, these files were located under /usr/local/etc/

The could be determined by typing
odbcinst -j

Which yielded:

unixODBC 2.3.0
DRIVERS............: /usr/local/etc/odbcinst.ini
SYSTEM DATA SOURCES: /usr/local/etc/odbc.ini
FILE DATA SOURCES..: /usr/local/etc/ODBCDataSources
USER DATA SOURCES..: /usr/local/etc/odbc.ini
SQLULEN Size.......: 8
SQLLEN Size........: 8
SQLSETPOSIROW Size.: 8

My odbc.ini files already exists in /etc, so the solution was to copy them over over from /etc/ to /usr/local/etc/

cp /etc/odbc.ini /etc/odbcinst.ini /usr/local/etc/

Edit: It's also worth noting that the path outputted by the odbcinst -j command can change depending on using sudo or not.

回答3:

For me, it was all down to a single whitespace character.

$cat /home/ec2-user/.odbc.ini
[DSNNAME]
Driver =FreeTDS
Description=description
Server =serverpath
Port =1433
Database =dbname

Gave me the “Data source name not found, and no default driver specified” error.

Removing all the whitespaces before the '=' character made it work.

On a secondary note, using osql for DSN connection testing gives you a much more verbose description of any errors. It helped me a lot in the process.

$ osql -S DSNNAME -U username -P password
checking shared odbc libraries linked to isql for default directories...
    trying /txM ... no
    trying /tmp/sql ... no
    trying /tmp/sql ... no
    trying /w}H ... no
    trying /usr/loc ... no
    trying /tmp/sql.log ... no
    trying /home ... no
    trying /.odbc.ini ... no
    trying /usr/local/etc ... OK
checking odbc.ini files
    reading /home/ec2-user/.odbc.ini
[DSNNAME] found in /home/ec2-user/.odbc.ini
found this section:
    [DSNNAME]
    Driver =FreeTDS
    Description=description
    Server =serverpath
    Port =1433
    Database =dbname

looking for driver for DSN [DSNNAME] in /home/ec2-user/.odbc.ini
  no driver mentioned for [DSNNAME] in .odbc.ini
looking for driver for DSN [default] in /home/ec2-user/.odbc.ini
osql: error: no driver found for [DSNNAME] in .odbc.ini

Comparing the error message against my ini file made triaging the issue a lot easier.

回答4:

For others troubleshooting this same generic error, ensure that you didn't accidentally add extraneous characters at the top of your odbc.ini file - which causes it to be invalid and all data-source declarations to be silently ignored (the error giving no indication of the specific problem).

回答5:

I have the same problem. It turns out that the data source file missed: /etc/ODBCDataSources. Just touch that file and it works.