SELECT 
  1 
FROM 
  tmall_lock_keys 
WHERE 
  key_id = '9c788f59cb29fbfbe1e9258222e0b6c29064647c1e03952031f186f031fd7a61' 
  AND token = 'YDo50M3/BznlBDk+bq+phIyf8FBsf39HyFGYgdK5tZ8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00919

JSON explain

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