wip: Optimization for cassandra extid reading to avoid an extra index
wip because it does not work for now
Depends on !718 (closed)
Test Plan
tox (fails for now hence the wip stuff)
Migrated from D6263 (view on Phabricator)
wip because it does not work for now
Depends on !718 (closed)
tox (fails for now hence the wip stuff)
Migrated from D6263 (view on Phabricator)