public override bool Equals(object obj)
{
if (!(obj is ColumnFragment)) return false;
ColumnFragment column = obj as ColumnFragment;
if (column.PropertyFragment != null && PropertyFragment != null)
return column.PropertyFragment.Equals(PropertyFragment);
if (column.TableName != TableName) return false;
if (column.ColumnName != ColumnName) return false;
if (column.ColumnAlias != ColumnAlias) return false;
return true;
}
}