public async Task AddAsync(UniqueStoreItem item, CancellationToken cancel)
        {
            using (var db = await _db.CreateAsync(cancel).ConfigureFalse())
            {
                using (var t = db.BeginTransaction())
                {
                    if (await db.IsDuplicateOperationAsync(item.ToIdempotencyId(), cancel))
                    {
                        return;
                    }

                    try
                    {
                        item.Uniques
                        .Select(d => new UniqueStoreRow(item.EntityId, d.Scope, d.Aspect, d.Value, item.Bucket))
                        .ForEach(row => db.Insert(row));

                        t.Commit();
                    }
                    catch (DbException ex) when(db.IsUniqueViolation(ex))
                    {
                        throw new UniqueStoreDuplicateException(ex.Message);
                    }
                }
            }
        }
        private Task Insert()
        {
            var item = new UniqueStoreItem(_entityId, Guid.NewGuid()
                                           , new UniqueValue("test", scope: Scope)
                                           , new UniqueValue("test-p", OtherAspect, scope: Scope)
                                           );

            return(_sut.AddAsync(item, CancellationToken.None));
        }