SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '34fe7287ec79d8ef2452e1894faf6d194d06adc201f81bf452316aee376ec269' 
  AND token = 'Stl3UpoAYgzdRCCvs2UjckzLRCAFfdijRAukTub9vnA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}