Hi Tim,
Thanks for posting this question. It looks like our documentation is missing a key point:
If a resource is in the segments list for the FROM resource, then including that resource in your query will automatically exclude zero impression rows.
For this case, you can see the list of
segments for
extension_feed_item by going to
this page and expanding the
Segments in the first section. You'll see there that
ad_group and
campaign are listed.
I'll make a note that we need to clarify this in our docs.
If you want to see the association between a feed item and campaigns or ad groups, you can use the campaign_extension_setting or ad_group_extension_setting resources instead.
Cheers,