SQLite Forum

Adding table is not issue.Insert don't have issue. Case is failing on read
  var messageActual = (string)queryCommand.ExecuteScalar();

Here is updated test case

        public void Test_Read_Uncommited()
        {
            var connectionString = $"Data Source ={_dbFile}; Cache = Shared; read_uncommitted = true;";
            using (var firstConnection = new SQLiteConnection(connectionString))
            {
                try
                {
                    firstConnection.Open();                            
                    using (var firstTransaction = firstConnection.BeginTransaction())
                    {
                        string message = "Hello World!";
                        using (var createTable = firstConnection.CreateCommand())
                        {
                            createTable.CommandText = "CREATE TABLE Message(Text TEXT) ";
                            createTable.ExecuteNonQuery();
                        }
                        using (var insertRow = firstConnection.CreateCommand())
                        {
                            insertRow.CommandText = $"INSERT INTO Message ( Text ) VALUES ( '{message}' ); ";
                            insertRow.ExecuteNonQuery();
                        }
                        using (var secondConnection = new SQLiteConnection(connectionString))
                        {
                            try
                            {
                                secondConnection.Open();
                                //using (var secondTransaction = secondConnection.BeginTransaction(System.Data.IsolationLevel.ReadUncommitted))
                                {
                                    var queryCommand = secondConnection.CreateCommand();
                                    queryCommand.CommandText = "SELECT Text FROM Message;";
                                    var messageActual = (string)queryCommand.ExecuteScalar();
                                    Assert.IsTrue(string.CompareOrdinal(message, messageActual) == 0);
                                }
                            }
                            finally
                            {
                                secondConnection.Close();
                            }
                            firstTransaction.Rollback();
                        }
                    }    
                }
                finally
                {
                    firstConnection.Close();
                }         
            }
        }