SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f5d50412352d95101afda254c51c4ba07aa751de4f7b464f5b4c93eaa6a4757d' 
  AND token = 'vN/M8Zr6FrV6/7FGI7saAqJ/KB/MET3CDnmvlkmKHv8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00040

JSON explain

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