Re: Crash on SRF execution

Hi,

On 2015-03-15 17:59:39 +0200, Itai wrote:
> Thanks for the quick response!! :)
> But I don't get it... isn't:
> if (SRF_IS_FIRSTCALL()){
> }
> the iterator one time
> "initialization block" where I setup the data to be iterated
> upon?
>
> Can you please elaborate on how should I fix this? I'm probably missing something basic...

> > > if (SRF_IS_FIRSTCALL())
> > > {
> > > length = 4000;
> > > base_num = 1203000000;
> > > list = (NumberList *)palloc(sizeof(NumberList));
> > > list->pp_numbers = (Number **)palloc(sizeof(Number*) * length);

You allocate memory in the per call context here.

> > > list->length = length;
> > > i = 0;
> > > for (; i < length; i++)
> > > {
> > > num = (Number *)palloc(sizeof(Number));
> > > num->value = base_num + i;
> > > num->is_even = ((base_num + i) % 2 == 0) ? 1 : 0;
> > > list->pp_numbers[i] = num;
> > > }
> > > ereport(INFO, (errmsg("----------- data source -----------")));
> > > i = 0;
> > > for (; i < length; i++)
> > > {
> > > ereport(INFO, (errmsg("value: %d", list->pp_numbers[i]->value)));
> > > ereport(INFO, (errmsg("is_even: %d", list->pp_numbers[i]->is_even)));
> > > }
> > >
> > > funcctx = SRF_FIRSTCALL_INIT();
> > > oldcontext = MemoryContextSwitchTo(funcctx->multi_call_memory_ctx);

Because you only switch the memory context here. Move this up, to the
beginning of the SRF_IS_FIRSTCALL block. Before the palloc()s.

Greetings,

Andres Freund

--
Andres Freund http://www.2ndQuadrant.com/
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