Per https://www.mediawiki.org/wiki/Wikidata_query_service/User_Manual#Search_within_box and https://phabricator.wikimedia.org/T139823
the following should be supported
wikibase:cornerSouthWest The south-west corner of the box.
wikibase:cornerNorthEast The north-east corner of the box.
wikibase:cornerSouthEast The south-east corner of the box.
wikibase:cornerNorthWest The north-west corner of the box.
This feature request suggests to add the following:
wikibase:cornerWest A west corner of the box.
wikibase:cornerEast An east corner of the box.
Depending on the https://en.wikipedia.org/wiki/Latitude value, the server would determine if it was S or N.
If latitude of W > latitude of E = W is NW, E is SE,
otherwise it's SW and NE.
Sample query, based on the current sample one, should give comparable results:
Schools between San Jose, CA and Sacramento, CA
#defaultView:Map
SELECT * WHERE {
wd:Q986857 wdt:P625 ?SJloc .
wd:Q17152020 wdt:P625 ?SCloc .
SERVICE wikibase:box {
?place wdt:P625 ?location .
bd:serviceParam wikibase:cornerWest ?SJloc .
bd:serviceParam wikibase:cornerEast ?SCloc .
}
?place wdt:P31/wdt:P279* wd:Q3914 .
}