CODEWITHSUNDEEP
c#entity-frameworklinq
Tân
Tân

Reputation: 1

EF - Update multiple rows in database without using foreach loop

My test code:

using (var db = new MyDbContext())
{
  string fromUser = ""; //sender
  string toUser = ""; //receiver

  var messages = db.Message.Where(x => x.FromUser == fromUser && x.ToUser == toUser)
                 .ToList();

  foreach (var message in messages)
  {
    message.IsRead = true;
    db.SaveChanges();
  }
}

My question: is there another way to update database without using foreach loop in that case?

p/s: I'd been reference these questions but all of them didn't solve my problem:

Upvotes: 12

Views: 22855

Answers (2)

Scott R. Frost
Scott R. Frost

Reputation: 2061

Just to update Steve's answer, in newer EF (current EF Core 3.1.3) you can do it all as one statement.

await db.Message.Where(m => m.FromUser == fromUser && m.ToUser == toUser).ForEachAsync(m => m.IsRead = true);
await db.SaveChangesAsync().ConfigureAwait(false);

Upvotes: 8

Steve Greene
Steve Greene

Reputation: 12324

You don't need to SaveChanges() on each iteration. That will hit the database multiple times. Try:

using (var db = new MyDbContext())
{
  string fromUser = ""; //sender
  string toUser = ""; //receiver
  var messages = db.Message.Where(x => x.FromUser == fromUser && x.ToUser == toUser)
                 .ToList();
  messages.ForEach(m => m.IsRead = true);
  db.SaveChanges();
}

Upvotes: 27

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