hi guys,
does anybody know the structure of the table that records people's activities on those SNS websites? e.g. facebook, when people perform some operations, there will be a message like "Person A uploads a photo", and their friends will know what they've done. I think there must be a table recording this. thanks

yes, there is a table recording it

thanks for the response. but do you know what its structure is? I guess it may be Activity(activityId, operatorId, operatedObject, objectId,...). if any wrong, please correct me.

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Wasn't the structure of facebook given in this thread?

no. the thread you referred to is about how to store the relationship. my present question is about how to store the user's activity. they're different

If it's not in the original facebook database then can't you just get a bit creative and create a table called UserActivity and simply store what the user does. You might want a flag to indicate whether to notify friends or not so important things can get notified out while lesser things might just be logged. You might want to include some form of optional id field etc to indicate what photo has been uploaded. Now when the user does anything interesting you can tell his friends about that activity ie

Code:

create table UserActivity (
  user_id
  activity_description
  notify_flag
  time_completed
)

insert UserActivity values ( 1234, 'added new photo',1,now() )

thank mike_bike_kite. I think I got a little process on it.
Activity(activityId, operatorId, activity_description, operatedObject, objectId, happenTime). but it is not perfect.

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