SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'f3596c3d092d9c34967c3c6778fc952afb30b2d32de1b4a17d7cadbcde422074' 
  AND token = 'MeY9YxjRqFghMN8XKaB4SzOKwbR/ULnTJ+CP194Z2w8=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00048

JSON explain

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