How facebook manages user profiles in database?

Question

E.g. I've 350 friends mapped in my profile, so it's not necessarily all my friends' data stored in single data store. So how facebook maps all my connections when I load my profile, in real time? Do they use, trie data structure/graph data structure?

Solution

Like mentioned in the comments, only FB programmers would know the specifics. Second best alternative would be to read their engineering page:

https://www.facebook.com/Engineering

Regarding your query, following post should give you some insight:

https://www.facebook.com/notes/facebook-engineering/tao-the-power-of-the-graph/10151525983993920

also check:

https://www.facebook.com/notes/facebook-engineering/linkbench-a-database-benchmark-for-the-social-graph/10151391496443920

There are many other posts which gives insight about their infrastructure, benchmarking, caching etc. You could search for more information.

Comments

[jobin]

Are you sure you are stuck, the terminal does not display the password, nor does it show * in place of characters you type? Press enter after you have typed your password to confirm you are stuck.

[Mad_Dave]

Control+C clears the "freeze" but I can still not complete any code that requires the password - Just a white flashing box after the :

[web.learner]

Possible Duplicate: askubuntu.com/q/112069/44179

[Eliah Kagan]

It appears you may simply not have been typing in your whole password before pressing enter. When you type in your password, ignoring that nothing seems to be happening while you do so, and then after typing in the whole password press Enter, what happens? Is that what you've been doing? (If so, see this answer.) Or when you're told to "try again" is that after pressing enter without first putting in your whole password? Unless you can provide more information, we should probably go ahead and close this as a duplicate, as @Seth suggested.

[Barmar]

They almost certainly use a relational database.

[Barmar]

If you mean what kind of data structures they use in the application after querying the database, no one here is likely to be able to answer that. Only the FB programmers know the specifics.

[chrylis -cautiouslyoptimistic-]

@Barmar Facebook most certainly doesn't use a relational database; it's probably the most pathological single application ever for such a data structure. It uses a custom graph store.

[chrylis -cautiouslyoptimistic-]

This question appears to be off-topic because it is about internal Facebook data structures.

[jobin]

@Mad_Dave, the message "Sorry, try again" appears when the password you have typed is not what you provided while installing Ubuntu or after you have changed in your "Accounts". Do you correctly remember your password? If not, you can try recovery options: askubuntu.com/questions/24006/…, but first confirm you are typing your correct password where it asks you to, though you won't be able to see the password you are typing for security reasons.

[Mad_Dave]

Password is fine as I use it when asked to authenicate when adding software. White box just flashes at me and does not move. If it does accept the enter I get the Sorry try again message

[gertvdijk]

@EliahKagan From the report that JamesR404 can right-click (only) to paste, he's using a completely different Terminal, maybe even PuTTY. The confusion started when this answer seemed not to match the situation of OP. I sort-of-answered the question in a comment here. I believe there's something you're missing: that the cursor isn't moving while typing the password.