SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = 'f37c0a97d810d81632adb7c01a5c760b43003874f212ea4fe839326a87335cb0' 
  AND token = 'TmwzWNJ737UgdAJcDKVPvul1qF2xT9Sg6jPuRyJRshI=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00030

JSON explain

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