SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f157608908d8f585952ab319437795284efed6667dd85ff9cf5d43e1636ce468' 
  AND token = 'yWgG1sWsSapWI8O77B84AsEVC6kxoK5rUbO2+YYFEcg=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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