SELECT 
  1 
FROM 
  tmall_lock_keys 
WHERE 
  key_id = '0fd3117225309c2050ab1aeab304502a442a6bf6d7f0d443eaf6e3937b674d2d' 
  AND token = 'iQ+281ZAHbgsmURpy4kSPIN4QZJJQppzQ6hW21cWmKA=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00859

JSON explain

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