SqlConnection nwindConn = new SqlConnection("Data Source=localhost;Integrated Security=SSPI;Initial Catalog=northwind");
SqlDataAdapter custDA = new SqlDataAdapter("SELECT CustomerID, CompanyName FROM Customers ORDER BY CustomerID", nwindConn);
// The Update command checks for optimistic concurrency violations in the WHERE clause.
custDA.UpdateCommand = new SqlCommand("UPDATE Customers (CustomerID, CompanyName) VALUES(@CustomerID, @CompanyName) " +
"WHERE CustomerID = @oldCustomerID AND CompanyName = @oldCompanyName", nwindConn);
custDA.UpdateCommand.Parameters.Add("@CustomerID", SqlDbType.NChar, 5, "CustomerID");
custDA.UpdateCommand.Parameters.Add("@CompanyName", SqlDbType.NVarChar, 30, "CompanyName");
// Pass the original values to the WHERE clause parameters.
SqlParameter myParm;
myParm = custDA.UpdateCommand.Parameters.Add("@oldCustomerID", SqlDbType.NChar, 5, "CustomerID");
myParm.SourceVersion = DataRowVersion.Original;
myParm = custDA.UpdateCommand.Parameters.Add("@oldCompanyName", SqlDbType.NVarChar, 30, "CompanyName");
myParm.SourceVersion = DataRowVersion.Original;
// Add the RowUpdated event handler.
custDA.RowUpdated += new SqlRowUpdatedEventHandler(OnRowUpdated);
DataSet custDS = new DataSet();
custDA.Fill(custDS, "Customers");
// Modify the DataSet contents.
custDA.Update(custDS, "Customers");
foreach (DataRow myRow in custDS.Tables["Customers"].Rows)
{
if (myRow.HasErrors)
Console.WriteLine(myRow[0] + "\n" + myRow.RowError);
}
protected static void OnRowUpdated(object sender, SqlRowUpdatedEventArgs args)
{
if (args.RecordsAffected == 0)
{
args.Row.RowError = "Optimistic Concurrency Violation Encountered";
args.Status = UpdateStatus.SkipCurrentRow;
}
}
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