How to update MS Access database

Question

I need a simple program to update MS Access database fields. I followed an online tutorial which was simple and had the code working. But it doesnt seem to work anymore when I reimplement it. Here's my code.

 public partial class Form1 : Form
 {
    public Form1()
    {
        InitializeComponent();
    }

    OleDbConnection conn;
    OleDbDataAdapter da;
    DataSet ds;
    OleDbCommandBuilder cb;
    DataRow row;

    private void Form1_Load(object sender, EventArgs e)
    {
        conn = new OleDbConnection("PROVIDER=Microsoft.Jet.OLEDB.4.0; Data Source = C:\\test.mdb");
        da = new OleDbDataAdapter("select* from user", conn);
        ds = new DataSet();

        conn.Open();
        da.Fill(ds, "user");
        conn.Close();
    }

    private void button1_Click(object sender, EventArgs e)
    {
        cb = new OleDbCommandBuilder(da);
        row = ds.Tables["user"].Rows[0];

        row[3] = "hello";

        da.Update(ds, "user");
    }
}

user is the table name of my database. What I tried to do is update the field row[0] (first row) and column[3] (4th column) with the string hello .. The error i get is Synatx error in FROM clause . After some internet reading, I found user has to be in square brackets. So I made it this.

public partial class Form1 : Form
{
    public Form1()
    {
        InitializeComponent();
    }

    OleDbConnection conn;
    OleDbDataAdapter da;
    DataSet ds;
    OleDbCommandBuilder cb;
    DataRow row;

    private void Form1_Load(object sender, EventArgs e)
    {
        conn = new OleDbConnection("PROVIDER=Microsoft.Jet.OLEDB.4.0; Data Source = C:\\test.mdb");
        da = new OleDbDataAdapter("select* from [user]", conn);
        ds = new DataSet();

        conn.Open();
        da.Fill(ds, "user");
        conn.Close();
    }

    private void button1_Click(object sender, EventArgs e)
    {
        cb = new OleDbCommandBuilder(da);
        row = ds.Tables["user"].Rows[0];

        row[3] = "hello";

        da.Update(ds, "user");
    }
}

When I do this, I get a new error, Syntax error in UPDATE statement . I did a lot of internet reading but none seems to address this. They all have used Update command differently. I know only this way. What's wrong in my code? Especially since this worked before. Or isn't this way of updating a proper technique? Please help me with the code and not technical terms which I don't follow. Or any other procedure to update in ms access?

Thanks.

Answer 1

I've never tried to access an Access database with a .NET DataSet before, but I think you could replace the code in button1_Click with something like this:

private void button1_Click(object sender, EventArgs e)
{
   conn.Open();

   string query = "UPDATE [user] SET [columnname] = ? WHERE id = ?";
   var accessUpdateCommand = new OleDbCommand(query, conn);
   accessUpdateCommand.Parameters.AddWithValue("columnname", "hello");
   accessUpdateCommand.Parameters.AddWithValue("id", 123); // Replace "123" with the variable where your ID is stored. Maybe row[0] ?
   da.UpdateCommand = accessUpdateCommand;
   da.UpdateCommand.ExecuteNonQuery();

   conn.Close();
}

Yes, I know you'd be losing some of the benefits of the DataSet , but research suggests that the regular OleDbDataAdapter.Update function doesn't play well with Access.

Answer 2

student = txtStudent.Text;
            age = txtAge.Text;
            address = txtAddress.Text;
            section = CBSection.Text;



            string ConnectionString = @"Provider=Microsoft.ACE.OLEDB.12.0;Data Source=|DataDirectory|\STI.accdb";
            string queryString = "UPDATE Details set StudentName='"+student+"',Age='"+age+"',Address='"+address+"' where Section/Course="+section+"";
            OleDbConnection connection = new OleDbConnection(ConnectionString);
            OleDbCommand command = new OleDbCommand();
            command.CommandType = CommandType.Text;
            command.CommandText = queryString;
            command.Connection = connection;
            connection.Open();
            {
                try
                {
                    command.ExecuteNonQuery();
                    MessageBox.Show("StudentName : " + student + "\nAge : " + age + "\nAddress : " + address + "\nSection : " + section + "\nHas been successfully Enrolled");
                }
                catch (Exception ex)
                {
                    MessageBox.Show(ex.Message);
                }
            }*strong text*