[BUG] Deleting a non existing collection causes insert operation to fail

[alierdogan70]

Version
LiteDb 5.0.8.0
.net RunTime v4.0.30319
VS 2019
Windows Forms Application

Describe the bug

Deleting a non existing collection causes insert operation to fail. InsertBulk returns successful result but data do not get inserted to the database.

public class AddressOfflineReporsitory : IAddressOfflineReporsitory
{      
    public async Task<int> InsertAddresses(IList<Address> addresses)
    {
        var Result = 0;
        await Task<int>.Run(() =>
        {
            using (var db = LiteDBClient.CreateCon(LiteDBClient.DBType.CustomerAccount))
            {
                db.BeginTrans();
                var col = db.GetCollection<Address>();
                col.EnsureIndex(a => a.Name);
                col.EnsureIndex(a => a.No);
                col.EnsureIndex(a => a.Contact);
                Result = col.InsertBulk(addresses);
                db.Commit();
            }

        });
        return Result;
    }

    public async Task DeleteAllAddresses()
    {
        await Task.Run(() =>
        {
            using (var db = LiteDBClient.CreateCon(LiteDBClient.DBType.CustomerAccount))
            {
                
                var col = db.GetCollection<Address>();
                col.DeleteAll();
            }
        });
    }
}

Usage

await addressOfflineReporsitory.DeleteAllAddresses();
var savedcount = await addressOfflineReporsitory.InsertAddresses(ServiceResult.Data.ToList());
logger.Information("{AddressBookRecordCount} Address entry downloaded and saved.", savedcount);

Expected behavior
Data to be inserted. Insertbulk method returns correct number although data is not inserted.

Additional context
It works as expected when you change delete method as :

if (!db.CollectionExists(nameof(Address))) return;
var col = db.GetCollection<Address>();
col.DeleteAll();

[lbnascimento]

@alierdogan70 I could not reproduce the issue running LiteDB v5.0.8 on .NET Core v3.1.4.

Also, if I understood you correctly, you claim to be using .NET Framework 4.0, which I believe is not possible for two reasons:

1. LiteDB v5.0.x dropped support for .NET Framework 4.0;
2. You use async/await, which was only introduced in C# 5, and .NET Framework 4.0 only supported C# 4.

[alierdogan70]

Hi @lbnascimento

It is the runtime (CLR) version:

Target Framework is : 4.7.2

Sorry for the confusion.

---

It is not very easy to reproduce the issue. Insert operation needs to be runned immediately after the delete operation as in the example on a brand new database. When I stop the flow during debugging I see database-log file being generated but it disappears after the insert operation.

[lbnascimento]

@alierdogan70 I still haven't been able to reproduce the issue. I'm running on .NET Framework 4.7.2 and I tried running both in debug and in release mode.

The log file is meant to disappear when the LiteDatabase is disposed.

Try calling db.Checkpoint() right after db.Commit().

[alierdogan70]

Hi @lbnascimento ,

I created a small application containing the bug. Please delete the database file before every try. If you uncomment AddressRepository.cs line 95 it works properly.

LiteDBInsertBulk.zip

I hope this helps

[lbnascimento]

@alierdogan70 This seems to be related to #1762, and your app finally allowed me to reproduce it and to fix it, so thanks for that.

Just to make sure, could you test with the latest master?

[sinanbuyukbayrak]

@lbnascimento I am having the same problem although I tried with latest master.
.net 5-rc1, vs 2019 preview.

using var db = new LiteDatabase(new ConnectionString
{
      Filename = "C:\\testing\\taskdb.ld",
      Password = "xxx",
      Connection = ConnectionType.Shared,
      ReadOnly = false
});

var collection = db.GetCollection<BasicGuidValue>("task_guid");

Guid taskMainGuid = Guid.Parse("ac2b28f7-bce7-441c-adbb-7f3e62c89c5c");
var guidBasic = new BasicGuidValue(taskMainGuid);

collection.DeleteAll();
collection.Insert(guidBasic);

// BasicGuidValue obj ->

public class BasicGuidValue
{
     [JsonConstructor]
     [BsonCtor]
     public BasicGuidValue(Guid value)
     {
         Value = value;
     }

     public Guid Value { get; set; }
}

After the code runs, the collection is not created in the database (If not exists).
When I remove DeleteAll code line, perfectly created the collection in the database.

--

Same problem, different delete strategy;

using var db = new LiteDatabase(new ConnectionString
{
      Filename = "C:\\testing\\taskdb.ld",
      Password = "xxx",
      Connection = ConnectionType.Shared,
      ReadOnly = false
});
db.DropCollection("task_guid");
var collection = db.GetCollection<BasicGuidValue>("task_guid");

Guid taskMainGuid = Guid.Parse("ac2b28f7-bce7-441c-adbb-7f3e62c89c5c");
var guidBasic = new BasicGuidValue(taskMainGuid);

collection.Insert(guidBasic);

Still not creating the collection.

[lbnascimento]

@alierdogan70 I could not reproduce the issue on .NET Core 3.1. I'm not currently able to test on .NET 5 (I may be in a few days). Is there any way you could test it with .NET Core 3.1?

[alierdogan70]

@alierdogan70 I could not reproduce the issue on .NET Core 3.1. I'm not currently able to test on .NET 5 (I may be in a few days). Is there any way you could test it with .NET Core 3.1?

Hi. I am out of town for 3 weeks. I am going to try when I return back.