SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '230261a5e9dccf6d03b8963780f632adaf498898de48e8c024c0d787e423d735' 
  AND token = 'KybOvOuIfsTAxuI76XYPpTTFRWt7OVkBS05jsgBD9xM=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00044

JSON explain

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