SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '063fc69d4a10f66bcd89ca949b1fa910db6edecae26557ee8ec909cffb99ef09' 
  AND token = 'h6ugz5VmE8YGlsI/4VwKDGoWlxUf0ZIDUrpqPQQeUwM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00026

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}