Is this conflict behavior normal?

[kmgallahan]

Hi. I have a fairly standard setup, but I'm getting conflicts with ConflictType == RemoteExistsLocalExists with doc comment:

  /// <summary>
  /// The Remote and Local datasources have both updated the same row.
  /// </summary>

My setup and steps that produce the conflict:

• 2 clients, both using SqliteSyncProvider
• 1 server, using SqlSyncChangeTrackingProvider
• Both clients are fully up-to-date with entire database synced locally

1. Client A updates a row in local DB
2. Client A syncs row update to server
3. Client B runs periodic sync and sees the update
4. Client B reports a conflict of type RemoteExistsLocalExists

So even though client B has not changed the row in its local DB, it is still reported as a conflict here. Is that normal?

[Mimetis]

You may have modify Client B row, otherwise it's a normal sync
Can you provide a sample that can easily reproduce the error ?

[kmgallahan]

@Mimetis Do you suspect or have you determined that this is an issue with the SqliteSyncProvider provider or rather the SqlSyncChangeTrackingProvider provider?

I can swap providers on the server side as a temporary fix if that is the case.

[kmgallahan]

I tested with SqlSyncProvider in my sample app, same conflicts. So I presume SqliteSyncProvider is bugged and not working at intended.

@Mimetis Should I create an issue for this since it appears to be a bug rather than expected behavior?

[Mimetis]

Sorry for the soooo lonnnng delay before answering (too much work ....)

First of all, a big thank you for the so detailed, easy to use, easy to run, sample you've provided

I've tried it, and indeed I've a conflict raised.

I don't know why and need to investigate.
Meanwhile, you can use a new agent each time you're making a sync

From your code, I've modified your Task:

async Task RunSyncAsync()
{
    try
    {
        var agent2 = new SyncAgent(clientProvider, serverProvider)
        {
            Options =
            {
                UseVerboseErrors = true,
            },
        };

        await syncLock.WaitAsync();
        var result = await agent2.SynchronizeAsync(setup);
        Console.WriteLine($"[{DateTime.Now}] Sync Result: {result}");
    }
    catch (Exception ex)
    {
        Console.WriteLine($"[{DateTime.Now}] Sync Error: {ex.Message}");
    }
    finally
    {
        syncLock.Release();
    }
}

[Mimetis]

No, the issue is still occuring
Seems we have a problem with the tracking row creation in SQLITE.

Let's continue the conversation here : #1373

[kmgallahan]

@Mimetis I am actually already running a local build of the lib with the code fix from #1373.

Seems we have a problem with the tracking row creation in SQLITE.

I think you forgot about the built-in maintenance that cleans up old tracking rows automatically. Refer to my reply in the open issue.