Deferrable Constraints

Dear Friends,

Can someone explain to me about deferable constraints? enable novalidate and others . Its really confusing for me.

I am not so clear.

Here is a question.

create table prices
(product_name varchar2(30),
 price number(10,4));

Table created.

alter table prices add constrint pk_prices_01 primary key (product_name);

Table altered;

insert into prices values ('DOGGY', 499.99);

1 row created.

alter table prices disable constraint pk_prices_01;

Table altered.

insert into prices values ('DOGGY' 449.99);

1 row created.

alter table prices enable novalidate constraint pk_prices_01;

What happens next?

I just typed the question has I got the answer wrong so would like to know if someone can explain how it actually works. I thought It will not verify the existing entries but will verify the upcoming records but the answer was wrong.

Thanks.

Qurious to know the answer.

I am held up as my desktop computer has got into some problem so I couldn't try them out myself. The question has nothing about deferable but I am confused about that too. Would be glad if someone can try to explain it to me.

BigLearner Received on Sat Dec 02 2006 - 01:34:45 CST