Inserting data into a MySql table which changes dynamically through Java

Can you help me with my problem of inserting rows to a table whose columns/ fields change dynamically. I have a table named schedule, in which depending the fields increase or decrease dynamically. My requirement is to insert data into this table. The problem is that, I am unsure of how many fields are there, because, it increases or decreases dynamically.

My idea: I have used ResultSetMetaData to dynamically know the field names. With this, I can use the insert query which wil be like:

ResultSet res = stat.executeUpdate("insert into scheduletab (name,date,shift,'"+col_name[i]+"') values (....., ...., .....)");

The problem here is that how will I initialize or specify the value of "i" ?

My code is :

Note: b34 is the button to submit.

if (e.getSource() == b34)
{
    String[] col_name = new String[25];
    try
    {
        Class.forName("com.mysql.jdbc.Driver");
        Connection con = DriverManager.getConnection(
           "jdbc:mysql://localhost/nursedb", "root", "123456");
        try
        {
            Statement st = con.createStatement();
            ResultSet rs = st.executeQuery("SELECT * FROM scheduletab");
            ResultSetMetaData md = rs.getMetaData();
            int col = md.getColumnCount();
            System.out.println("Number of Column : " + col);
            System.out.println("Columns Name: ");
            for (int i = 1; i <= col; i++)
            {
                col_name[i] = md.getColumnName(i);
                System.out.println(col_name[i]);
            }
        }
        catch (SQLException s)
        {
            System.out.println("SQL statement is not executed!");
        }

        // Start Inserting data into Schedule Tab by specifying the
        // column names.
        Statement stat = con.createStatement();
        // ResultSet res =
        // stat.executeUpdate("insert into scheduletab (name,date,shift,'"values();
        // End Inserting data into Schedule Tab by specifying the column
        // names.

    }
    catch (Exception ex)
    {
        ex.printStackTrace();
    }
}