Sandbox

SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'e94348218efe57abfc99e32cc448cd52f131b42ed5242c8ddcce8bda403c4dda' 
  AND token = 'fLoRl9OAkrbWBDjUXEqS9caavttoswmESHTslJA0GmA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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