SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'dababfb1eb939a50cd21bdcae2edbd7cf32b7f1667de24a917ca1f2188858c18' 
  AND token = '2eq0JVZDIEaVvUMhTxe05r8prCh8xmtl4UNjWP8NrHk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00035

JSON explain

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