Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '21d4cdf26ab141ab2b69aa57642cd2f7560f73c6519acc6d027ddf8a882ae58c' 
  AND token = '5ET0dQMAJ1eSnsaovXBezS1mclPXYelXuN7onn2h2Do=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

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