1. Command Object’s ExecuteNonQuery Method
ISYS 512

2. Using ExecuteNonQuery Method
To run SQL:
Insert
Delete
Update
The ExecuteNonQuery method also returns a value indicating the number of records affected by the SQL statement.

3. Use ExecuteNonQuery to Insert A New Record
Create unbound text boxes to enter new customer record.
string strConn = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=C:\\CSharpexamples\\SalesDB2011.accdb";
OleDbConnection objConn = new OleDbConnection(strConn);
string strSQLInsert;
strSQLInsert = "Insert into Customer values ('";
strSQLInsert += textBox1.Text + "','" + textBox2.Text + "','";
strSQLInsert += textBox3.Text + "','" + textBox4.Text + "')";
OleDbCommand objCommInsert= new OleDbCommand(strSQLInsert, objConn);
objConn.Open();
MessageBox.Show(strSQLInsert.ToString());
try {
objCommInsert.ExecuteNonQuery(); }
catch (Exception ex)
MessageBox.Show(ex.Message);
objConn.Close();

4. Use ExecuteNonQuery to Delete A New Record
Create a listbox with CIDs
Delete the selected record and remove the CID from the listbox.
string strConn = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=C:\\CSharpexamples\\SalesDB2011.accdb";
OleDbConnection objConn = new OleDbConnection(strConn);
string strSQL = "delete from customer where cid = '" + listBox1.SelectedItem + "'";
OleDbCommand objComm = new OleDbCommand(strSQL, objConn);
try {
int affectedRecords;
objConn.Open();
affectedRecords= objComm.ExecuteNonQuery();
MessageBox.Show(affectedRecords.ToString() + "records deleted");
listBox1.Items.RemoveAt(listBox1.SelectedIndex); }
catch (System.Exception ex)
MessageBox.Show(ex.Message);
objConn.Close();

5. Use ExecuteNonQuery to Update A New Record
Create a project that do the following tasks:
Use a DataReader to retrieve customer IDs and populate a listbox.
Select a new rating from radio buttons for the selected customer.
Update customer’s rating using the ExecuteNonQuery method of a Command object.
, fa n

6. create CID listbox:
private void Form4_Load(object sender, EventArgs e) {
string strConn = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=C:\\CSharpexamples\\SalesDB2011.accdb";
OleDbConnection objConn = new OleDbConnection(strConn);
string strSQL = "select cid from customer;";
OleDbCommand objComm = new OleDbCommand(strSQL, objConn);
try
objConn.Open();
OleDbDataReader objDataReader;
objDataReader = objComm.ExecuteReader();
while (objDataReader.Read() == true)
listBox1.Items.Add(objDataReader["cid"]); }
catch (System.Exception ex)
MessageBox.Show(ex.Message);
objConn.Close();

7. Update customer rating:
private void button1_Click(object sender, EventArgs e) {
string newRating;
if (radioButton1.Checked)
newRating = "A"; }
else if (radioButton2.Checked)
newRating = "B";
else
newRating = "C";
string strConn = "Provider=Microsoft.ACE.OLEDB.12.0;Data Source=C:\\CSharpexamples\\SalesDB2011.accdb";
OleDbConnection objConn = new OleDbConnection(strConn);
string strSQL = "Update customer set rating = '" + newRating + "' where cid='" + listBox1.SelectedItem + "'";
OleDbCommand objComm = new OleDbCommand(strSQL, objConn);
try
objConn.Open();
objComm.ExecuteNonQuery();
catch (System.Exception ex)
MessageBox.Show(ex.Message);
objConn.Close();