help with good way to perform SQL queries programatically (and my failed attempt to use OData)

Question

I'll give you the context of what I was doing in case anyone wants to offer suggestions for the best route I might take to achieve my goal, which is to have easy access to do queries on the newish stachexchange data.

I first looked for the data dump but found it isn't very new (Aug 2012).

I then found the online interface to enter sql queries and I was happy that I could get results pretty easily. Here's the query I did:

with T as (
  select top 100 Users.Id UserId, count(Posts.Id) NumPosts
  from Users
  inner join Posts on Users.Id = Posts.OwnerUserId
  group by Users.Id, Users.Reputation
  order by Reputation desc
)
select top 100 percent *
from T, Users
where Users.Id = T.UserId
order by Users.Reputation desc

However, I saw nothing in the FAQ this was an API.

Finally, I found the OData endpoint and gave that a try but found that a query to count posts with a given OwnerUserId randomly throws an exception that only says "see the server logs for more info". Since it was random I wrote some retry logic.

class Row
        {
            public int Id { get; set; }
            public string Name { get; set; }
            public int Points { get; set; }
            public int PostCount { get; set; }
        }

        [TestMethod]
        public void GetRows()
        {
            var context = new Entities(new Uri("http://data.stackexchange.com/stackoverflow/atom"));
            var topUsers = context.Users.OrderByDescending(c => c.Reputation).Take(50);
            Func<int, int> postCount = (id) =>
            {
                Thread.Sleep(1000);
                try
                {
                    return context.Posts.Where(c => c.OwnerUserId == id).Count();
                }
                catch
                {
                    return -1;
                }
            };
            var topUsersWithPostCount =
                    from u in topUsers.AsEnumerable().Where(c => c.Id != 157882)
                    select new Row
                    {
                        Id = u.Id,
                        Name = u.DisplayName,
                        Points = u.Reputation ?? 0,
                        PostCount = postCount(u.Id)
                    };
            var ok = topUsersWithPostCount.ToLookup(c => c.PostCount != -1);
            int tries = 1;
            int maxTries = 5;
            while (true)
            {
                Console.WriteLine("retrying..");
                var retry = from item in ok[false]
                            select new Row
                            {
                                Id = item.Id,
                                Name = item.Name,
                                Points = item.Points,
                                PostCount = postCount(item.Id)
                            };
                var result = ok[true].Concat(retry);
                if (result.Any(c => c.PostCount == -1) && tries++ < maxTries)
                    continue;
                result.ToList().ForEach(c => Console.WriteLine("{0},{1},{2}", c.Id, c.Name, c.PostCount));
                break;
            }
        }

Without the 1sec pause it goes past max number of retries.

Is there a limit to number of requests in a time period? Alternately, is there a way I could have achieved the same result with fewer requests? I tried using .Any but it returned a "OData must be version 3" error.