SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '27e15ed7eacbdd313eef1ac21cce962df489c882bbfafb2135bc91c755ae590a' 
  AND token = 'vkyhCHM9Wm96gq1b+o1b+R5c10zK6JPMi1JiJtZe1e0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00043

JSON explain

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