Re: Update on tables when the row doesn't change

Dawid Kuroczko wrote:
> On 5/24/05, Sebastian Böck <sebastianboeck(at)freenet(dot)de> wrote:
>
>>/* 3rd way of separating updates
>> con: unnecessary updates on tables
>> pro: view gets evaluated only 1 time
>>
>> Not adressing the problem of unnecessary updates, but the view
>> gets only evaluated one time.
>>
>>*/
>>
>>CREATE OR REPLACE FUNCTION upd (view_test) RETURNS VOID AS $$
>> DECLARE
>> NEW ALIAS FOR $1;
>> BEGIN
>> RAISE NOTICE 'UPDATE';
>> UPDATE test SET test = NEW.test WHERE id = OLD.id;
>> UPDATE join1 SET text1 = NEW.text1 WHERE id = OLD.id;
>> UPDATE join2 SET text2 = NEW.text2 WHERE id = OLD.id;
>> UPDATE join3 SET text3 = NEW.text3 WHERE id = OLD.id;
>> RETURN;
>> END;
>>$$ LANGUAGE plpgsql;
>
>
> Control question, I didn't check it, but would it be enough to change from:
> UPDATE join1 SET text1 = NEW.text1 WHERE id = OLD.id;
> to:
> UPDATE join1 SET text1 = NEW.text1 WHERE id = OLD.id AND text1 <> NEW.text1?
>
> ... I may be wrong. :)

Yes, thats more elegant then my other (4th) solution.
Was late yesterday evening ;)

Thanks

Sebastian