Social activity stream and wall (wall)

Question

MySQL

I don’t know yet how to translate “social activity stream” into Russian, so that it’s clear what is at stake, so I’ll leave this term as it is. Those things that I will write about - I have not yet implemented, so I can make a lot of mistakes. Now to the question. The fact is that the “social activity stream” is a kind of log of user actions, i.e. the user created a post, wrote a news item, added a picture, created a poll, etc. “Wall” (wall) is also a log of user actions, but actions are already grouped, i.e. writing on the wall - this can be the entry itself, several photos, several notes, etc.

How to design a database for "activity stream" and "wall" - it seems to be clear.

The question is whether a social network (as on fb or vk) needs the presence of both “activity stream” and “wall”, since the first is the system log, and the second is the log that users will see.

The question is more of a philosophical nature, or something, i.e. to understand the very concept of the structure of the corresponding part of the database of a small social network.

Answer 1

At the expense of grouping in the wall table, everything is not so smooth, because if a record collects, for example, all notes added by the user for an hour / day, then the question is how such posts will look like, say, for yesterday, provided that half of the photos / notes , specified in the record, deleted? In this case, it is necessary for each wall message to either check the availability of each element listed in it during the output, or don't give a damn, but then the result will be appropriate.
The activity stream is not very important, unless it will keep discrete records, for example, the creation of one photo / note, just for the log. Alternatively, you can store a wall_message_id in it, which will point to the grouped post in which this action will be displayed. Then the process that I wrote about above is a little easier, since, for example, when deleting a photo, we can find a write-back (creation) in the activity stream table, select wall_message from there, from which we can already delete that very photo from the listed group.