SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '16cd8164dfa6bbd9d57b101af80b98960941c62e077437eeaf07587a6b124af7' 
  AND token = 'P7ltg0VZeXnHbVhZZABIoHa53bmj9dXxOXuiEXRtccw=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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