Forum OpenACS Q&A: Transactions in PL/PgSQL ?

Did anyone ever get transactions to work in plpgsql? I am trying the following, which works fine with out the transaction statements:

begin transaction;

insert into ms_customer_credit_ledger (ledger_id,
 credit_id, type_id, amount, description)
values (nextval(''ms_credit_ledger_seq''),v_credit_row.credit_id,
 4,v_credit_total ,''credit for item '' || 
 NEW.item_id);

update ms_customer_credit 
 set balance = (balance - v_credit_total)
where
 credit_id = v_credit_row.credit_id;

commit;

Alternatively, can I wrap the tcl code in a transaction and have it work?

I think what I am lead to believe by these statements is that, for instance, if I call a function, all the dml gets executed, or rolled back? If a sql statement inserts data into one table, which fires a trigger which inserts data into another table, will the whole thing rollback if the second insert fails? I actually have two levels of triggers in one case, where the second insert fires a second trigger which updates a third table.