SELECT 
  1 
FROM 
  tmall_lock_keys 
WHERE 
  key_id = '6c39c838dad330cc29d483b03773051b52f92c7510ff5a1fcb6dbc1ebd46aa0c' 
  AND token = 'FB+oXSIfGKBu+JnzFvBV0B+1/6zzsdbhbLTwqvWgFW8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00862

JSON explain

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