By using the SQL statement INSERT INTO, and executeNonQuery just like you
do.

If you don't want to insert values into a database you must enable NULL's in
the datafield in the table. When you insert data into the table, don't use
the filed in the INSERT INTO statement. You can do that by building the SQL
statement dynamically by using string handling. (Please use
System.Text.StringBuilder for speed).

Here is an example I just wrote. This is a J# win app exe for simplicity.

Open a new J# "Windows application" and replace the code in the "Form1" with
this code. This code will produce the SQL statement dynamically.

The code is straight forward, it could also be done more dynamically by Eg.
using the tags in the GUI.

package DynamicSQL;

import System.Drawing.*;
import System.Collections.*;
import System.ComponentModel.*;
import System.Windows.Forms.*;
import System.Data.*;

public class Form1 extends System.Windows.Forms.Form
{
private System.Windows.Forms.TextBox textBox1;
private System.Windows.Forms.TextBox textBox2;
private System.Windows.Forms.TextBox textBox3;
private System.Windows.Forms.TextBox textBox4;
private System.Windows.Forms.TextBox textBox5;
private System.Windows.Forms.Button button1;
private System.ComponentModel.Container components = null;

public Form1()
{
 InitializeComponent();
}

protected void Dispose(boolean disposing)
{
 if (disposing)
 {
  if (components != null)
  {
   components.Dispose();
  }
 }
 super.Dispose(disposing);
}

#region Windows Form Designer generated code
/**
 * Required method for Designer support - do not modify
 * the contents of this method with the code editor.
 */
private void InitializeComponent()
{
 this.textBox1 = new System.Windows.Forms.TextBox();
 this.textBox2 = new System.Windows.Forms.TextBox();
 this.textBox3 = new System.Windows.Forms.TextBox();
 this.textBox4 = new System.Windows.Forms.TextBox();
 this.textBox5 = new System.Windows.Forms.TextBox();
 this.button1 = new System.Windows.Forms.Button();
 this.SuspendLayout();
 //
 // textBox1
 //
 this.textBox1.set_Location(new System.Drawing.Point(30, 24));
 this.textBox1.set_Name("textBox1");
 this.textBox1.set_TabIndex(0);
 this.textBox1.set_Text("");
 //
 // textBox2
 //
 this.textBox2.set_Location(new System.Drawing.Point(30, 56));
 this.textBox2.set_Name("textBox2");
 this.textBox2.set_TabIndex(1);
 this.textBox2.set_Text("");
 //
 // textBox3
 //
 this.textBox3.set_Location(new System.Drawing.Point(30, 88));
 this.textBox3.set_Name("textBox3");
 this.textBox3.set_TabIndex(2);
 this.textBox3.set_Text("");
 //
 // textBox4
 //
 this.textBox4.set_Location(new System.Drawing.Point(30, 120));
 this.textBox4.set_Name("textBox4");
 this.textBox4.set_TabIndex(3);
 this.textBox4.set_Text("");
 //
 // textBox5
 //
 this.textBox5.set_Location(new System.Drawing.Point(30, 152));
 this.textBox5.set_Name("textBox5");
 this.textBox5.set_TabIndex(4);
 this.textBox5.set_Text("");
 //
 // button1
 //
 this.button1.set_Location(new System.Drawing.Point(43, 192));
 this.button1.set_Name("button1");
 this.button1.set_TabIndex(5);
 this.button1.set_Text("button1");
 this.button1.add_Click( new System.EventHandler(this.button1_Click) );
 //
 // Form1
 //
 this.set_AutoScaleBaseSize(new System.Drawing.Size(5, 13));
 this.set_ClientSize(new System.Drawing.Size(160, 230));
 this.get_Controls().Add(this.button1);
 this.get_Controls().Add(this.textBox5);
 this.get_Controls().Add(this.textBox4);
 this.get_Controls().Add(this.textBox3);
 this.get_Controls().Add(this.textBox2);
 this.get_Controls().Add(this.textBox1);
 this.set_Name("Form1");
 this.set_Text("Form1");
 this.ResumeLayout(false);

}
#endregion

/**
 * The main entry point for the application.
 */
/** @attribute System.STAThread() */
public static void main(String[] args)
{
 Application.Run(new Form1());
}

private void button1_Click (Object sender, System.EventArgs e)
{
 System.Text.StringBuilder _sql = new System.Text.StringBuilder( );
       _sql.Append( "INSERT INTO table " );

 System.Text.StringBuilder _stat1 = new System.Text.StringBuilder();
 if ( !this.textBox1.get_Text().Equals( "" ) ) _stat1.Append( "Entity1" );
 if ( !this.textBox2.get_Text().Equals( "" ) )
 {
  if ( _stat1.get_Length() > 0 ) _stat1.Append( ", Entity2" );
  else _stat1.Append( "Entity2" );
 }
 if ( !this.textBox3.get_Text().Equals( "" ) )
 {
  if ( _stat1.get_Length() > 0 ) _stat1.Append( ", Entity3" );
  else _stat1.Append( "Entity3" );
 }
 if ( !this.textBox4.get_Text().Equals( "" ) )
 {
  if ( _stat1.get_Length() > 0 ) _stat1.Append( ", Entity4" );
  else _stat1.Append( "Entity4" );
 }
 if ( !this.textBox5.get_Text().Equals( "" ) )
 {
  if ( _stat1.get_Length() > 0 ) _stat1.Append( ", Entity5" );
  else _stat1.Append( "Entity5" );
 }

 System.Text.StringBuilder _stat2 = new System.Text.StringBuilder();
 if ( !this.textBox1.get_Text().Equals( "" ) )
 {
  if ( _stat2.get_Length() > 0 ) _stat2.Append( ", " +
this.textBox1.get_Text() );
  else _stat2.Append( this.textBox1.get_Text() );

 }
 if ( !this.textBox2.get_Text().Equals( "" ) )
 {
  if ( _stat2.get_Length() > 0 ) _stat2.Append( ", " +
this.textBox2.get_Text() );
  else _stat2.Append( this.textBox2.get_Text() );

 }
 if ( !this.textBox3.get_Text().Equals( "" ) )
 {
  if ( _stat2.get_Length() > 0 ) _stat2.Append( ", " +
this.textBox3.get_Text() );
  else _stat2.Append( this.textBox3.get_Text() );
 }
 if ( !this.textBox4.get_Text().Equals( "" ) )
 {
  if ( _stat2.get_Length() > 0 ) _stat2.Append( ", " +
this.textBox4.get_Text() );
  else _stat2.Append( this.textBox4.get_Text() );
 }
 if ( !this.textBox5.get_Text().Equals( "" ) )
 {
  if ( _stat2.get_Length() > 0 ) _stat2.Append( ", " +
this.textBox5.get_Text() );
  else _stat2.Append( this.textBox5.get_Text() );
 }

 if ( _stat1.get_Length() == 0 ) System.Windows.Forms.MessageBox.Show( "No
SQL statements can be made" );
 else
 {
  _sql.Append( "(" +_stat1.ToString() + ")" );
  _sql.Append( " VALUES " );
  _sql.Append( "(" + _stat2.ToString() + ")" );
  System.Windows.Forms.MessageBox.Show( _sql.ToString() );
 }
}
}

Regards,
Lars-Inge Tønnessen