Lets imagine situation: you have node event and node article. Event node have no references to article, only article have reference to event. You need to put one event field on each article which have reference to that event. Maybe I am wrong (please correct me if it is not true) but we are not able to do it in views module. There were couple modules which allow backreference, but in fact we don't need to install new module to have this functionality. We can make it in small custom module, lets call it it backreference block. Code example given above.
There are couple ways how to create content type programmatically. We can use hook_update_N() or hook_install()
Hi! When we use continuous integration and work on multiple environments at once we need to set all our changes itno code. Sometimes features module help us with this, sometimes we need to use update hooks. In case of xmlsitemap module we need to use update hooks. If we need to set priority on content type or delete content type from sitemap.xml file we can use code given below. On picture you can see administration interface of xmlsitemap module yoursite.com/admin/config/search/xmlsitemap/settings.
Hi, sometimes we need to do something extra, especially when we need to make some SEO. In drupal we have wonderfull xmlsitemap module. So sometimes an output of this module is not very good for us. We need to change priorities and change frequencies. Good news for us is that to set priority we can use administration interface, but frequency can be set only for front page. Some taxonomy pages also could be changed frequently but xmlsitemap module don't use it.