SELECT 
  1 
FROM 
  cscart_multi_declock_keys 
WHERE 
  key_id = '2ee67dc91561d4198bc2b0fbba5f431d3548603d33b51485f250f80961e6154a' 
  AND token = 'GtNuZY2vs3Pmzs9ZunL7sYRfr+sRiPHJUKKIErxqP9c=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00028

JSON explain

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