Join Count attribute

BlakeMorrison

I'm trying to automate a regular workflow via Data Pipelines. The current workflow I follow involves performing a spatial join, then filtering for join_count and performing different actions depending on the join count.

 

I might be misunderstanding something here, but I can only get a join count using one-to-one, and the attributes aren't actually joined together in the table - I only have the original feature attributes and an extra join count field.

 

If I perform a one-to-many join I can access the joined attributes, but I don't have a join count field to filter by.

 

Am I missing something here? Is there another way to achieve this workflow?

MaxPayson

Hi @BlakeMorrison, one-to-one joins create summarized values for all "Join" dataset records that match a single "Target" dataset record, so it doesn't return the "Join" attribute values themselves. By default, the only summary statistic is the count, but more can be added with the "Summary fields" parameter. Then one-to-many joins create a new record for each matching "Join" dataset record, but they don't summarize so they don't include the count.

A couple ideas to accomplish what you described:

1. For the 0 match case, use "One to many" and "Left join", then use the Filter by attribute tool to filter to the records where the joined fields are empty (no match) or where they are not empty (match)
2. For the generic case, add a "One to one" join to create the count, then add a "One to many" join with the original dataset and "One to one" output as inputs. This should add the count back to the original records

Let us know if this helps! And thank you for the question