/// <summary>
/// Uses a reliable connection retry policy and transaction
/// scoping to add and submit a set of EntityObjects. Submits items
/// a page at a time.
/// </summary>
/// <typeparam name="T">Must derive from <typeparamref name="EntityObject"/>.</typeparam>
/// <param name="context">Any ObjectContext</param>
/// <param name="objects">A set of <typeparamref name="EntityObject"/>s to save.</param>
/// <param name="pageSize">The number of items to submit at one time.</param>
public static void AddObjectsAndSave <T>(
this ObjectContext context, IEnumerable <T> objects, int pageSize = 1000, Action <IEnumerable <T> > doThisInstead = null)
where T : EntityObject
{
if (!objects.Any())
{
return;
}
var name = context.GetTableName <T>();
var watch = new Stopwatch();
var times = new List <TimeSpan>();
int page = 1;
PaginatedList <T> items = null;
var hasNextPage = true;
while (hasNextPage)
{
//reset watch
watch.Reset();
watch.Start();
//get page of items and save them
items = new PaginatedList <T>(objects.AsQueryable(), page, pageSize);
hasNextPage = items.HasNextPage;
if (doThisInstead != null)
{
doThisInstead(items);
}
else
{
context.AddObjectsAndSave(items);
}
page++;
//record time
watch.Stop();
times.Add(watch.Elapsed);
Console.Write("{0}: {1} rows in {2}.",
name,
items.Count,
watch.Elapsed.ToPrettyString());
Console.WriteLine(" Page {0}/{1}, {2} complete, ETA: {3}.",
items.PageNumber,
items.TotalPages,
((double)items.PageNumber / (double)items.TotalPages).ToString("P"),
DateTime.Now.AddSeconds(
times.Average((ts) => ts.TotalSeconds) *
(items.TotalPages - page)).ToLongTimeString());
}
Console.WriteLine("{0} done! Took {1}.",
name,
TimeSpan.FromSeconds(times.Sum((ts) => ts.TotalSeconds)).ToPrettyString());
}
public static void AddObjectsAndSaveWithIdentityInsert <T>(
this ObjectContext context, IEnumerable <T> objects)
where T : EntityObject
{
if (!objects.Any())
{
return;
}
Action <IEnumerable <T> > exec = (obj) =>
{
var policy = new RetryPolicy <SqlAzureTransientErrorDetectionStrategy>
(10, TimeSpan.FromSeconds(10));
var name = context.GetTableName <T>();
foreach (var item in obj)
{
context.AddObject(name, item);
}
policy.ExecuteAction(() =>
{
context.Connection.Open();
var trans = context.Connection.BeginTransaction();
context.ExecuteStoreCommand("SET IDENTITY_INSERT " + context.GetTableName <T>() + " ON");
context.SaveChanges();
context.ExecuteStoreCommand("SET IDENTITY_INSERT " + context.GetTableName <T>() + " OFF");
trans.Commit();
context.AcceptAllChanges();
context.Connection.Close();
});
};
context.AddObjectsAndSave(objects, doThisInstead: exec);
}
