Sandbox

SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'bef99eb258b843630e1a6a11cab715b900938b4c8c779a6520923da1506df6a5' 
  AND token = 'q3N84NfRDE/ERAd4rUiOOhplak2NjultnqCynKtHBN8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00029

JSON explain

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