(SELECT read, write, version, create_time, update_time FROM ins)
UNION ALL
(SELECT read, write, version, create_time, update_time FROM storage WHERE collection = $1 AND key = $2 AND user_id = $3 AND version = $5 AND read = $6 AND write = $7)
LIMIT 1`
// Outcomes:
// - NoRows - insert was ignored due to constraint violation (concurrent insert or non-OCC existing row)
// - Row is returned if object was new or if object already existed but had the same values being inserted
// - NoRows - insert was ignored due to constraint violation (concurrent insert or non-OCC existing row), and values being inserted were different from existing row