how do i get id of the last inserted row

Question

i want to display booking id of the last inserted row.my insert code is given below. pls anyone can give me code to display the id

    protected void Button1_Click(object sender, EventArgs e)
    {
        string cs = ConfigurationManager.ConnectionStrings["connectionString"].ConnectionString;
        using (SqlConnection con = new SqlConnection(cs))
        {
            SqlCommand cmd;
            SqlDataReader dr;
            con.Open();
            cmd = new SqlCommand("insert into [booking] values('" + TextBox1.Text + "','" + TextBox2.Text + "','" + TextBox3.Text + "','" + TextBox4.Text + "','" + TextBox5.Text + "','" + TextBox6.Text + "','" + TextBox7.Text + "','" + TextBox8.Text + "','" + TextBox9.Text + "','" + TextBox10.Text + "','" + TextBox11.Text + "')", con);

            cmd.ExecuteNonQuery();

        }
    }

Answer 1

I would suggest using something like this:

protected void Button1_Click(object sender, EventArgs e)
{
    var cs = ConfigurationManager.ConnectionStrings["connectionString"].ConnectionString;
    using (var con = new SqlConnection(cs))
    {
        con.Open();
        var cmd = new SqlCommand(
            "DECLARE @IDReturnTable TABLE( ID INT ); INSERT INTO [booking] OUTPUT INSERTED.NameOfYourIdColumn INTO @IDReturnTable VALUES(@param1, @param2, @param3); SELECT ID FROM @IDReturnTable", 
            con);
        cmd.Parameters.Add("@param1", SqlDbType.VarChar).Value = TextBox1.Text;
        cmd.Parameters.Add("@param2", SqlDbType.VarChar).Value = TextBox2.Text;
        cmd.Parameters.Add("@param3", SqlDbType.VarChar).Value = TextBox3.Text;

        var returnedId = cmd.ExecuteScalar();
    }
}

I didn't use all 11 Text Boxes, just 3 to illustrate the technique.

Answer 2

You will be better off doing this as a stored procedure, and less susceptible to injection.

---

To achieve it with your current code, add a call to ;SELECT SCOPE_IDENTITY() :

cmd = new SqlCommand("insert into [booking] values('" + TextBox1.Text + "','" + TextBox2.Text + "','" + TextBox3.Text + "','" + TextBox4.Text + "','" + TextBox5.Text + "','" + TextBox6.Text + "','" + TextBox7.Text + "','" + TextBox8.Text + "','" + TextBox9.Text + "','" + TextBox10.Text + "','" + TextBox11.Text + "');SELECT SCOPE_IDENTITY()", con);

And execute as scalar :

var id = cmd.ExecuteScalar();

(This assumes you have an identity column on your table)

---

To do it as a stored procedure:

If you have a finite number of values, you can just create the stored procedure normally, with an @Parameter for each TextBox.Text but with SELECT SCOPE_IDENTITY() at the end.

But it looks like you have a variable number of inputs, so see How to insert a multiple rows in SQL using stored procedures? which outlines an approach using a table paramater and one using a UDF to split a list of values.

Again, you would need to SELECT SCOPE_IDENTITY() at the end of the proc to pick up the identity of the last row.

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For a detailed discussion on the ways of selecting the last inserted id see What is the difference between Scope_Identity(), Identity(), @@Identity, and Ident_Current?