SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'a50828b90d12c50010dd47d2261ebf67125d6fb5a08506b3aed736b1e895e872' 
  AND token = 'v6aaneGlivX1O7lBFX5t59J6VQCiyqb6B9T4SVU13TY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00032

JSON explain

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