如何将Android与SQL Server数据库连接？

Question

I am getting problem in my application

Here is my piece of code my activity throwing an exception "Error Connection net.sourceforge.jtds.jdbc.Driver"

    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        sync = (Button) findViewById(R.id.button1);
        sync.setOnClickListener(new OnClickListener() {

            public void onClick(View arg0) {
                // TODO Auto-generated method stub
                query2(); }
        });
        }
    public void query2()
    {
    Log.i("Android"," SQL Connect Example.");
    Connection conn = null;
    try {
    String driver = "net.sourceforge.jtds.jdbc.Driver";
    Class.forName(driver).newInstance();
    //test = com.microsoft.sqlserver.jdbc.SQLServerDriver.class;
    String connString = "jdbc:jtds:sqlserver://server_ip_address         :198.168.0.10/tracebaledb;encrypt=fasle;user=sa;password=SqlServer2005;instance=SQLEXPRESS;";
    String username = "sa";
    String password = "SqlServer2005";
    conn = DriverManager.getConnection(connString,username,password);
    Log.w("Connection","open");
    Statement stmt = conn.createStatement();
    ResultSet reset = stmt.executeQuery("select * from AD_Login");

    //Print the data to the console
    while(reset.next()){
    Log.w("Data:",reset.getString(3));
                  Log.w("Data",reset.getString(2)); }
    conn.close();

    } catch (Exception e)
    {
    Log.w("Error connection","" + e.getMessage());
    }
    }    
}

Answer 1

You can connect to SQL Server databse throuh webservice.

Here is the sample code to call the webservice.

String url              = "your_webservice_URL";

 try 
 {
    HttpPost loginHttpPost   = new HttpPost(url); 
    HttpContext localContext = new BasicHttpContext();          

    MultipartEntity multipartContent = new MultipartEntity();
    multipartContent.addPart("parameter1", new StringBody(value1));
    multipartContent.addPart("parameter2", new StringBody(value2));
    loginHttpPost.setEntity(multipartContent);

    HttpClient objHttpClient = new DefaultHttpClient();
    HttpResponse response = objHttpClient.execute(loginHttpPost,localContext);
 } 
 catch (IOException e) {
     e.printStackTrace();

Make sure you set the permission in Manifest.xml file,

You can write the webservice in php or java to get this values and connect to SQL Server

Answer 2

An other approach is to use a Virtual JDBC Driver that uses a three-tier architecture: your JDBC code is sent through HTTP to a remote Servlet that filters the JDBC code (configuration & security) before passing it to the SQL Server JDBC Driver. The result is sent you back through HTTP. There are some free software that use this technique. This is secure because the database is never exposed directly and you may use SSL. Just Google "Android JDBC Driver over HTTP".