ODBC, 64 bit Linux

Question
ODBC is associated mostly with Windows platform but there exists also a Linux implementation of this API (http://www.unixodbc.org/). I was interested in answering the questions :

• How it runs on 64 bit Linux platform.
• Is it possible to develop multi-platform (Windows/Linux) C++ application having access to any data via ODBC driver provided.

How to answer ?

To answer that questions I had to develop a small wrapper around ODBC API. ODBC API is very complicated, I can hardly imagine any program littered with sequences: 

SQLAllocHandle - SQLSetEnvAttr - SQLConnect - SQLExecDirect - SQLFetch ....

To keep stuff as simple as possible I implemented only columns returned as string. I avoided problem with different data types and complicated C++ - SQL data types conversion. There is also nothing about  transactions, stored procedures, code pages, binding parameters etc. But I believe that this interface can be easily extended to meet more demanding requirements.

Solution, simple wrapper around C ODBC
ODBCDrivers.h

• getODBCDrivers : retrieves list of  ODBC drivers installed.
• getODBCDataSources : retrieves list of ODBC data sources.
• class ODBCConnection 
•    method open: opens connection
•    method execute : run SQL statements
•    method close: closes connection

 ODBCDrivers.cpp

In several places it was necessary to put statement like:

#ifdef WIN32
....
#endif

But test cases (look beneath) does not include anything like that, it is hidden behind facade (wrapper).

Test program

To test that interfaces and answer the questions set up above I created a program as a C++ unit test based on googletest framework.

The test cases are very simple:

Verify number of ODBC drivers available on the host.
testdrivers.cpp

Verify number of ODBC data sources available.
testdatasources.cpp

Main test

1. Create table
2. Add some tuples having columns like SYMBOL{number} and NAME{number}
3. Run some tests and verifications.

testconnection.cpp

Execute the test
I run the test on the following platforms:

Linux 64 bit (RedHat)

• Test program compiled as 64 bit application
• Database: Oracle 11g
• ODBC driver: EasySoft. I was unable to run Oracle ODBC driver.

Windows 64 bit (Windows 7)

• Test program compiled as 64 bit application (using MS Visual Studio 2008)
• Database: MySql 
• ODBC driver: MySql

Windows XP (32 bit)

• Test program compiled as 32 bit application (using MS Visual Studio 2008 Express)
• Database: DB2
• ODBC driver: DB2

Linux 32 bit (Ubuntu)

• Test program compiled as 32 bit application
• Database: Progress
• ODBC driver: Progress

Conclusion
So the answer is positive. It runs as expected on 64 bit linux. Also it is possible to have portable C++ code accessing database via ODBC API. This example is very simple but I dare say that this conclusion can be applied also for more serious applications.