Query mysql menghitung saldo per transaksi

CREATE TABLE `akuntansi`.`trx` (`nominal` float NOT NULL, `kode` CHAR(10) ;

INSERT INTO `akuntansi`.`trx` (`nominal`, `kode`) VALUES ('3434', 'k'), ('3434', 'k'), ('4434', 'k'), ('544', 'd'), ('453', 'd');

select @k:=if(kode="k",nominal,0) as Kredit,@d:=if(kode="d",nominal,0) as  debet, @s:=@s+@k-@d as saldo from trx;