SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '09ff80cd95778a0a0ae0359d77023428679d6bc96a384520de1167b1d1f5ebc3' 
  AND token = 'V0q9zwlb7EinmpBHytuGMgyjsbIOmGesPK/j8tgHbcU=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00024

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}