The most efficicient way to pick key,value from a large array

Now, we have a large array, contains user profile. [uid, username, password, email, qq, msn, skype, address, zipcode, telphone, mobile.......] We need to pick information from this big array, and we know the key we want to pick. What's the efficient way ? Is there any function like $pending_pick_key1 = [uid, username]; array_pick($origin_array, $pending_pick_key1); //return array contains [uid, username] $pending_pick_key2 = [username, password]; array_pick($origin_array, $pending_pick_key2); //return array contains [username, password] we current using array_filter and pass function into it to do this job. But it's not fast as we test. Any other ideas beside array_filter? Or we have to implement an php extension to do this job ? Sorry for trouble you. need your help. Appreciate your time. ---------------------------- Netroby