How to get a Random Object using Linq

Question

I am trying to get a random object within linq. Here is how I did.

//get all the answers
var Answers = q.Skip(1).Take(int.MaxValue);
//get the random number         


        

Answer 1

var rand = new Random();
var selectedPost = q.Skip(rand.Next(0, q.Count())).Take(1).FirstOrDefault();

Optimally, you want to only ever make the function query for a single value, so you set up the Skip/Take to jump up to the sequence number matching the random number you're generating (bounded by dataset's itemcount, so the missing row problem bounding based on MAX(pkey) isn't an issue) and then snag the first item at that point in the sequence.

In SQL this is the same as querying for SELECT Count(*) FROM q, then SELECT * FROM q LIMIT {0}, 1 where {0} is rand.Next(0, count), which should be pretty efficient.