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Python pyodbc - Error - [unixODBC][Oracle][ODBC][Ora]ORA-12162: TNS:net service name is incorrectly specified

By Dinesh


One may encounter below errors while connecting to oracle, using pyodbc, using python 3

  1. [unixODBC][Driver Manager]Can't open lib 'Oracle ODBC driver for Oracle 19' : file not found (0) (SQLDriverConnect)
  2.  [unixODBC][Oracle][ODBC][Ora]ORA-12162: TNS:net service name is incorrectly specified\n (12162) (SQLDriverConnect)
  3. RuntimeError: Unable to set SQL_ATTR_CONNECTION_POOLING attribute

The solution to fix above errors is to - 

  • Make following entry in /etc/odbcinst.ini
             [Oracle ODBC driver for Oracle 19]

            Description=Oracle ODBC driver for Oracle 19
            Driver=$ORACLE_HOME/lib/libsqora.so.19.1
            FileUsage=1
            Driver Logging=7
            UsageCount=1

  • Don't use following connect string - 
            import pyodbc
            myhost='<>'
            myservicename='<>'
            myuserid='<>'
            mypassword='<>'
            cnxn = pyodbc.connect('DRIVER={Oracle ODBC driver for Oracle 19};Direct=True;Host='+myhost+';Service Name='+myservicename+';User ID='+myuserid+';Password='+mypassword)

  • Instead use following connection String - 
            cnxn = pyodbc.connect('DRIVER={Oracle ODBC driver for Oracle 19};dbq='+myhost+':1521/'+myservicename+';uid='+myuserid+';pwd='+mypassword)


  • To execute SQL - 
            cursor = cnxn.cursor()
            cursor.execute("select 1 from dual;")
            row = cursor.fetchone()
            while row:
                print(row[0])
                row = cursor.fetchone()

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