Hello Again,
I looked into this for you and wanted to clarify something about our documentation, (which I agree is not as straightforward as it could be when describing fields and resources that are selectable together). For example the
campaign resource has a
Selectable With list, with the description,
"Artifacts (Resources, segments, or metrics) that can be used in the same SELECT clause." There's also the
Metrics list, with the description,
"Metrics that can be selected when this resource is specified in the FROM clause." Based on the query you shared earlier it seems like you want to reference the Metrics list, which does not include metrics.all_conversions_from_store_visit, so that's why you're receiving an error.
metrics.all_conversions_from_store_visit
are selectable from extension_feed_item, and since you can use metrics.all_conversions_from_store_visit and campaign in the same SELECT clause I believe you should be able to do something like:
SELECT
metrics.all_conversions_from_store_visit,
campaign.id
FROM extension_feed_item
WHERE
campaign.id = "< xyz >"
I'm not sure if you've already seen it, but we have a great interactive resource to help build queries. Take a look
here.
I hope that helps, please let me know if you have any other questions or trouble with this query.
Best,
Ben, Google Ads API Team

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