SELECT 
  1 
FROM 
  tmall_lock_keys 
WHERE 
  key_id = 'c73388667e2623763fc1b63526c46178831ade392a76169fc360c1b4875657ec' 
  AND token = 'j6+U9eWiqM/s1K2hULwFRtDgjUfuYOdQ4YUJZN9SKiY=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.01298

JSON explain

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