Question

I’ve got an assignment which requires me to update the northwind database,
I’ve done everything like the tutorials say as follows

I fill The DataTable Using The DataAdapter.Fill(table).

I build the Delete,Insert,Update Commands using CommangBuilder

SqlDataAdapter adapter = new SqlDataAdapter(selectStr, conn);
SqlCommandBuilder builder = new SqlCommandBuilder(adapter); 
adapter.DeleteCommand = builder.GetDeleteCommand(true);
adapter.UpdateCommand = builder.GetUpdateCommand(true);
adapter.InsertCommand = builder.GetInsertCommand(true);
adapter.Fill(employees_table);

I also set a primary key for the table:

DataColumn[] employees_keys = new DataColumn[2];
employees_keys[0] = employees.Columns["EmployeeID"];
employees_table.PrimaryKey = employees_keys; 

Now I’ve attempted to delete and add a row:

// accepts an employee object and creates a new new row with the appropriate values for 
// an employee table row 
DataRow row = ConvertEmployeeToRow(employeeToAdd);
employee_table.Rows.Add(row);`

and deleting a row:

DataRow row = employees.Rows.Find(employeeToDismiss.ID);
employees.Rows.Remove(row); 

I should also point out that I’ve attempted to use row.SetAdded() and row.Delete()

Anyway, at the end when I try to update the database

int k = employees_adapter.Update(employees_table);

on added rows sometimes k get valued, on remove never, and in either case nothing really gets updated at all in the database itself.

Any insight of what I’m doing wrong?

Answer 1

Make sure you’re calling employee_table.AcceptChanges() after the call to Update() to save the changes to the database.