calculation of IsNullable is not correct

[GoogleCodeExporter]

It may be more of a disagreement but if the item is not Nullable<T> and it is 
not typeof(string) or typeof(byte), one could argue the column is not nullable.

I added code in my example to perform this check after the !IsPk

                if (IsNullable && Nullable.GetUnderlyingType(prop.PropertyType) == null 
                        && ColumnType != typeof(string) && ColumnType != typeof(byte[])) {
                    IsNullable = false;
                }

public PropColumn(PropertyInfo prop) {
                _prop = prop;
                Name = prop.Name;
                //If this type is Nullable<T> then Nullable.GetUnderlyingType returns the T, otherwise it returns null, so get the the actual type instead
                ColumnType = Nullable.GetUnderlyingType(prop.PropertyType) ?? prop.PropertyType;
                Collation = Orm.Collation(prop);
                IsAutoInc = Orm.IsAutoInc(prop);
                IsPK = Orm.IsPK(prop);
                IsIndexed = Orm.IsIndexed(prop);
                IsNullable = !IsPK;
                MaxStringLength = Orm.MaxStringLength(prop);
            }

Original issue reported on code.google.com by joseph.f...@gmail.com on 4 Dec 2010 at 4:49