CREATE TABLE movimentos (numeros NUMBER, data date, num_conta char(6), valor number(12,2))

CREATE TABLE contas (numeros NUMBER, saldo number(12,2),titular char(30))

2 - (Sequence) 

CREATE SEQUENCE SEQ_numeros START WITH 1;

(trigeer)

CREATE OR REPLACE TRIGGER TRG_numeros
BEFORE INSERT ON movimentos
FOR EACH ROW
BEGIN
     SELECT SEQ_numeros.NEXTVAL INTO:NEW.numeros FROM DUAL;
END;



CREATE OR REPLACE TRIGGER TRG_SALDO
AFTER INSERT ON movimentos 
FOR EACH ROW
DECLARE
SALDOATU NUMBER;
BEGIN
     SALDOATU = select saldo from contas where numeros = :new.numeros
     update contas set saldo = saldoatu + :new.valor 
END; 


6 - 

CREATE OR REPLACE PROCEDURE DELETA_ANTIGO IS
BEGIN
	FOR DADOS IN (SELECT * FROM movimentos WHERE data > sysdate - 180) LOOP
		delete from movimentos;
	END LOOP;
	COMMIT;
END;


4 - insert into movimentos (0, sysdate, '66666666', 120.00)


3 - 

CREATE OR REPLACE TRIGGER TRG_SALDO
AFTER INSERT ON movimentos 
FOR EACH ROW
DECLARE
SALDOATU NUMBER;
BEGIN
     select saldo into SALDOATU from contas where numeros = :new.numeros;
     update contas set saldo = saldoatu + :new.valor;
END; 





 Se voceis forem copiar mude algumas coisas