SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ff153294a37fdcdb93a95b8ec356d82d57cf0cdb99c762c36f359615b059d0ed' 
  AND token = '7UydqgLXlEQBxgWdKdTSE2AR75J7Hz/xslupdX4weiM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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