Hi,
1. It is a filter that has basically nothing to do with blogs - it is again just a showcase of some functionality that may be used on the site. Using data sources and filters is described in this
chapter. In this case, the repeater has the filter specified in its properties and they communicate together when required.
2. This is standard .Net repeater thing - the control knows according to the path which transformation should be used.
3. The SQL in the repeater is just where condition for using tags. It is described in the Tags documentation and you would read it in case you are interested in using tags. Otherwise, it is not required. There is also a
DB manual available. However, it is really required when doing low level devleopment or customizations.
4. This is also one part how the repeater knows about the default and selected item transformation. The template is inherited due to the
Visual inheritance. Again, you can use separate templates with different web parts and their configuration. The easiest way is to use inherited template with the same set of the web parts.
In general, you need to create a document of CMS.Blog type, fill out the form. This is the particular blog landing page. You can use the pre-defined template or your custom. To list the blogs, you need to add a repeater (the idea is the same as in listing news - it does not matter what content you are listing, it is still the same). Then, the blogger will just select to create a "Blog post" document, fill out the data and that's it.
The rest is additional - custom look and feel, styling, using e.g. tagging, categories, filters, search, etc.
Best regards,
Juraj Ondrus