constchar*queryBefore="SELECT * FROM "KEYSPACE_NAME"."CF_SENSORDATA" WHERE sid = ? AND ws = ? AND ts <= ? ORDER BY ts DESC LIMIT "PSC_READ_BEHIND;
constchar*queryBefore="SELECT * FROM "KEYSPACE_NAME"."CF_SENSORDATA" WHERE sid = ? AND ws = ? AND ts <= ? ORDER BY ws DESC, ts DESC LIMIT "PSC_READ_BEHIND;
constchar*queryAfter="SELECT * FROM "KEYSPACE_NAME"."CF_SENSORDATA" WHERE sid = ? AND ws = ? AND ts > ? LIMIT "PSC_READ_AHEAD;