How to update the sitemap?

Question

Search Engine Optimization

Good day.
I have a self-written site and I made a module for working with a site map (xml)
Once in a while (I have it once a day), the map is completely recreated. Those. The urls of the corresponding posts on the site do not change in the current sitemap, everything is simpler - each time the map is completely deleted and a new sitemap.xml is created.
Questions
1) Is the logic supposed to be like this? Those. in fact, we create a new map every time? (And don't we work with the already created one, changing only some xml nodes in the once created file?)
2) How often should the map be created / recreated? Is there any recommended time interval?

Answer 1

It makes absolutely no difference whether you create a map again or add it to a file, it does not play any piano. The main thing is that the map is true and there are no dead/broken links in it.