FbTransaction dbtran = conn.BeginTransaction();
                FbCommand insertCommand = new FbCommand();
                insertCommand.CommandText = "insert into teachers(id_teacher, fio, post) values(@CodeOfTeacher, @FIO, @Post)";
                insertCommand.Connection = conn;
                FbCommand insertCommand2 = new FbCommand();
                insertCommand2.CommandText = "insert into teachersanddepartments(id_teacher, id_department) values(@CodeOfTeacher, @DepartmentCodeOfDepartment)";
                insertCommand2.Connection = conn;
                insertCommand.Transaction = dbtran;
                insertCommand2.Transaction = dbtran;
                insertCommand.Parameters.AddWithValue("@CodeOfTeacher", teacher.CodeOfTeacher);
                insertCommand.Parameters.AddWithValue("@FIO", teacher.FIO);
                insertCommand.Parameters.AddWithValue("@Post", teacher.Post);

                insertCommand2.Parameters.AddWithValue("@CodeOfTeacher", teacher.CodeOfTeacher);
                insertCommand2.Parameters.AddWithValue("@DepartmentCodeOfDepartment", teacher.Department.CodeOfDepartment);
                try
                {
                    int result = insertCommand.ExecuteNonQuery();
                    int result_2 = insertCommand2.ExecuteNonQuery();
                    dbtran.Commit();
                    insertCommand.Dispose();
                    insertCommand2.Dispose();
                    return result > 0 && result_2 > 0;
                }
                catch (Exception e)
                {
                    MessageBox.Show(e.Message);
                    dbtran.Rollback();
                    return false;
                }




//using (FbTransaction dbtran = conn.BeginTransaction())
                    //{
                    //    try
                    //    {
                    //        using (FbCommand insertCommand = new FbCommand())
                    //        {
                    //            insertCommand.CommandText = "EXECUTE BLOCK AS BEGIN " +
                    //                " EXECUTE STATEMENT 'insert into teachers (id_teacher, fio, post) values(@CodeOfTeacher, @FIO, @Post)';" +
                    //                " EXECUTE STATEMENT 'insert into teachersanddepartments (id_teacher, id_department) values((@CodeOfTeacher, @DepartmentCodeOfDepartment))';" +
                    //                "END";
                    //            insertCommand.Connection = conn;
                    //            insertCommand.Transaction = dbtran;

                    //            insertCommand.Parameters.AddWithValue("@CodeOfTeacher", teacher.CodeOfTeacher);
                    //            insertCommand.Parameters.AddWithValue("@FIO", teacher.FIO);
                    //            insertCommand.Parameters.AddWithValue("@Post", teacher.Post);
                    //            insertCommand.Parameters.AddWithValue("@DepartmentCodeOfDepartment", teacher.Department.CodeOfDepartment);

                    //            int result = insertCommand.ExecuteNonQuery();
                    //            dbtran.Commit();
                    //            return result > 0;
                    //        }
                    //    }
                    //    catch(Exception e)
                    //    {
                    //        MessageBox.Show(e.Message);
                    //        dbtran.Rollback();
                    //        return false;
                    //    }
                    //}