SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '141fb9e5183e613923b5845c0d2f42d9790c37550046fb83a2b43c9e0919dee8' 
  AND token = 'u8ZeTny+Y2n6gUemqtcGqu5PjykvRe7hmTj1sIibEVU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00033

JSON explain

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