SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '92b0aefa1f2822a3eb4a0025884565e8a8e60b328d22af80eb6be27663eda632' 
  AND token = 'XzYbpd9qWTjlcTIzHpRSyocf6uFnOLvElgYKtkiFgR0=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00039

JSON explain

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