odbc

Description:

odbc

dart-odbc allows you to connect to any database vendor with your legacy ODBC drivers.
Usage #
The library interface looks very similar to the original ODBC API:
http://msdn.microsoft.com/en-us/library/windows/desktop/ms710252(v=vs.85).aspx
Connect:
// Allocate an environment handle.
var hEnv = new SqlHandle();

sqlAllocHandle(SQL_HANDLE_ENV, null, hEnv);

// Set ODBC version to be used.
var version = new SqlPointer()..value = SQL_OV_ODBC3;

sqlSetEnvAttr(hEnv, SQL_ATTR_ODBC_VERSION, version, 0);

// Allocate a connection handle.
var hConn = new SqlHandle();

sqlAllocHandle(SQL_HANDLE_DBC, hEnv, hConn);

// Connect.
sqlConnect(hConn, "<YOUR DSN>", SQL_NTS, "<YOUR USER ID>", SQL_NTS, "<YOUR PASSWORD>", SQL_NTS);
copied to clipboard
Retrieve some data:
// Allocate a statement handle.
var hStmt = new SqlHandle();

sqlAllocHandle(SQL_HANDLE_STMT, hConn, hStmt);

// Prepare a statement.
sqlPrepare(hStmt, "SELECT name FROM customers WHERE customer_id = ?", SQL_NTS);

// Bind parameters.
var customerId = new SqlIntBuffer()..poke(<YOUR CUSTOMER_ID>);

sqlBindParameter(hStmt, 1, SQL_PARAM_INPUT, customerId.ctype(),
SQL_INTEGER, 0, 0, customerId.address(), 0, null);

// Bind result set columns.
var name = new SqlStringBuffer(32);
var flags = new SqlIntBuffer();

sqlBindCol(hStmt, 1, name.ctype(), name.address(), name.length(), flags.address());

// Execute and fetch some data.
sqlExecute(hStmt);

sqlFetch(hStmt);

...

// Free statement handle.
sqlFreeHandle(SQL_HANDLE_STMT, hStmt);
copied to clipboard
Disconnect:
// Disconnect.
sqlDisconnect(hConn);

// Free connection handle.
sqlFreeHandle(SQL_HANDLE_DBC, hConn);

// Free environment handle.
sqlFreeHandle(SQL_HANDLE_ENV, hEnv);
copied to clipboard
Note that error handling has been removed for clarity.
Take a look at the test folder for more examples.
Testing #
odbc_test, located at test folder, is a command line application that can be used to test the library with any database vendor.
Example:
dart odbc_test.dart --driver "Oracle in XE" --version 380 --dsn ODBC_TEST_ORACLE --uid odbc_test --pwd odbc_test
copied to clipboard
Execute odbc_test.dart without parameters to see details of usage.
Take a look at the schema folder to get the proper database schema to be used for testing.
Building #
ODBC binding is made with a Dart native extension, that is, a .dll (Windows), .so (Linux) or .dylib (Mac) file.
The source code is available, so you can build your own version.
Windows
Instructions to compile the native extension with Microsoft Visual C++ 2010 Express Edition:


Create a new Win32 DLL empty project
(File | New | Project)


Use "Multi-Byte Character Set" instead of "UNICODE"
(Configuration Properties | General | Character Set)


Add <YOUR DART SDK DIRECTORY>/include to VC++ include directories
(Configuration Properties | VC++ Directories | Include Directories)


Add <YOUR DART SDK DIRECTORY>/bin to VC++ library directories
(Configuration Properties | VC++ Directories | Library Directories)


Add dart.lib to additional dependencies
(Configuration Properties | Linker | Input | Additional Dependencies)


Add DART_SHARED_LIB and ODBC_EXTENSION_EXPORTS to preprocessor definitions
(Configuration Properties | C/C++ | Preprocessor | Preprocessor Definitions)


Copy all files from the cpp/src folder of the dart-odbc project to the "Source Files"


Compile it!


Linux
Instructions to compile the native extension with gcc:


Start a command line console in the cpp/src folder of the project


Compile sources with the following command:
g++ -fPIC -m32 -shared -O2 -I


Notes #


This package only includes the 32 bits Windows dll, but it can be used in 64 bits operating system.


If you use the Win32 version in a Win64 operating system just remember to use the Win32 ODBC administrator located at <YOUR WINDOW DIRECTORY>\SysWOW64\odbcad32.exe, instead of the one available under Windows Control Panel.