Using if-then-else-end in jq to handle missing values

This is the command I use to pull the info I need:

.results | .[] | {id, name: .general.name, platform: .general.platform, site: .general.site.name, ea_site: .extensionAttributes.[] | select(.definitionId=="57").values.[]}

When .extensionAttributes.[] | select(.definitionId=="57").values.[] is empty, jq does not display any associated items at all.

What I'd like to do is check if .extensionAttributes.[] | select(.definitionId=="57").values.[] < 0 and return empty otherwise return the content. I'm trying to use if-then-else-end, but can't seem to get the syntax correct.

You can find sample data in jqplay here.Line 1218 in the json input has the empty value.

Desired output:

{ "id": "3882", "name": "Kresge-iMac-900", "platform": "Mac", "site": "Arts", "ea_site": "Arts"}{ "id": "3881", "name": "c-loaner", "platform": "Mac", "site": ".Production", "ea_site": "blank"}