Read/Unread

[Cless]

Similar to a forum, I need an efficient way to check if a user has read a topic or has not read it. What would be the most efficient way to doing so?

[jackpf]

Is this short term or long term?

 

If it's the former, you could just save the ID's in a session.

 

If the latter, you'd have to have a table for storing usernames and topic ID's. Then query the database to see if the username and ID exist, if so, the user has read the topic.

 

That's hwo I'd do it anyway.

[Cless]

It is long term. I have also thought about doing sessions, but those would be short term.

 

I was also thinking of storing it like that, I am worried, however, that this could cause some MySQL lag. I almost have 100,000 users.

[RussellReal]

it shouldn't cause any lag, pull the data like you'd usually do.. and then

assuming in the field the ids would be seperated by commas, e.g.

1,17,23,30,20,10

if (in_array($this_user_id,explode(',',$row['viewed_by_id']))) {

  // user has viewed this topic

}

[Cless]

Ah yes, I've never thought of doing it in an array form. I'll try it out.

 

Thanks!