When dissolver a feature into its neighbour, I want the neighbour's attribution to win every time?

What do you have the accumulation mode set to?

If the drain attributes are not important I would remove all attributes except from those required in a group by and then choose Merge Incoming Attributes

Hi @ebygomm​ 

I've tried all accumulations, but generally go with 'Use attributes from one feature'. Results seem to be similar no matter which one I use, except 'Drop incoming features' which drops everything.

How can I define that the drain is the incoming attribute. There are multiple (35) other classes that the drain could be merging onto. Right now, I have a spatial relator which creates a relationship between the drain and its neighbouring class and then I merge using this group by ID. But I still get drains out.

Thanks for your help.

B

Yes, this ^

As per the Help/Documentation:

Attribute Accumulation Mode

Merge Attributes merges all attributes from overlapping segments. If there are conflicts, attributes from input polygons will be preserved in a two-step process:

• First, attributes from one of the polygons with the largest area will be copied onto the output polygon.
• Second, attributes from all other input polygons will be copied, without overwrite, onto the output polygon

If you remove all the Drain Feature Attributes with say, an AttributeRemover, then the Second step in the Merge Attribute process will not have any Attribute conflicts to resolve, so all Attributes in the output will be from a Neighbor Feature

Thanks @ebygomm​  and @bwn​. Removing the attributes worked. Thanks I appreciate your concise and prompt help.

B