Question

I am facing problem adding and deleting DataRows from a DataTable that is meant for DataAdapter.Update(). I keep getting Concurrency error but I cannot figure where is wrong.

It happens when i add and delete rows from a DataTable.

At the moment, I add rows like this:

table.Rows.Add(new string{null /*pk*/, "composite_FK1", "composite_FK2", "composite_FK3"});

and i delete the last logical row in the DataTable like this:

DataRow[] rows = table.Select(string.Empty, string.Empty, DataViewRowState.CurrentRows);

if (rows.Length > 0)
{
    DataRow row = rows[rows.Length - 1];
    if (row.RowState == DataRowState.Added)
    {
        // directly remove this row because it is not in the database yet
        table.Rows.Remove(row);
    }
    else
    {
        // mark this row for deletion from the database
        row.Delete();
    }
}

After a few add and deletes, Update fails with Concurrency Exception. What can be a better way to add rows? Anyone can help spot the error please? Thanks.

Answer 1

It is easier to write your data to the database (inserts or updates), then read the data back from the database into your data table.