Re: Suggestion for optimization

> I don't think your idea would work for a concurrent user setup where
> people have different transactions started at different times with
> different amounts of changes inside each transaction.
>
> That's why it would have to be tracked on a "per connection" basis for
> all the tables.

I tried it out with concurrent connections and it seemed to hold up just 
fine. I think MVCC took care of everything. Transactions got a different 
count depending on whether they could see the inserted values or not. Once 
committed all transactions could see the new table count.

Can you provide a case where it wouldn't?

I imagine this causes some major performance issues, not to mention the dead 
tuples would pile up fast, but it seems to work just fine. 

My SQL is below.

Regards,Jeff

jdavis=> create table tuple_count(tuples int);
CREATE
jdavis=> create table c1(a int);
CREATE
jdavis=> create function f1() returns opaque as '
jdavis'> BEGIN
jdavis'>      UPDATE tuple_count set tuples=tuples+1;
jdavis'>      RETURN NEW;
jdavis'> END;
jdavis'> ' language 'plpgsql';
CREATE
jdavis=> create function f2() returns opaque as '
jdavis'> BEGIN
jdavis'>      UPDATE tuple_count set tuples=tuples-1;
jdavis'>      RETURN NEW;
jdavis'> END;
jdavis'> ' language 'plpgsql';
CREATE
jdavis=> create trigger t1 after insert on c1 for each row execute procedure 
f1();
CREATE
jdavis=> create trigger t2 after delete on c1 for each row execute procedure 
f2();
CREATE