is it automatically written data to a pda account once you serialise it's data buffer?

Question

I am learning Solana from the soldev.app. The code is taken from the StateManagement tutorial. After the pda_account is deserialized, there is written new values into its buffer. Shouldn't be a method to commit the changes to the pda_account besides the serialize method? I'm asking because this is the example code of the tutorial, and this is how it ends.

let mut account_data = try_from_slice_unchecked::<MovieAccountState>(&pda_account.data.borrow()).unwrap();
account_data.title = title;
account_data.rating = rating;
account_data.description = description;
account_data.is_initialized = true;

//this is the line im reffering to
account_data.serialize(&mut &mut pda_account.data.borrow_mut()[..])?;

Answer 1

You need no more than the last line. The serialize method writes to the account you pass into its argument, updating it.