Re: BitmapHeapScan streaming read user and prelim refactoring

On 5/14/24 20:40, Melanie Plageman wrote:
> On Tue, May 14, 2024 at 2:33 PM Tomas Vondra
> <tomas(dot)vondra(at)enterprisedb(dot)com> wrote:
>>
>> On 5/14/24 19:42, Melanie Plageman wrote:
>>> I've fixed this. I've also set enable_material off as I mentioned I
>>> might in my earlier mail.
>>>
>>
>> I'm not sure this (setting more and more GUCs to prevent hypothetical
>> plan changes) is a good practice. Because how do you know the plan does
>> not change for some other unexpected reason, possibly in the future?
>
> Sure. So, you think it is better not to have enable_material = false?
>

Right. Unless it's actually needed to force the necessary plan.

>> IMHO if the test requires a specific plan, it's better to do an actual
>> "explain (rows off, costs off)" to check that.
>
> When you say "rows off", do you mean do something to ensure that it
> doesn't return tuples? Because I don't see a ROWS option for EXPLAIN
> in the docs.
>

Sorry, I meant to hide the cardinality estimates in the explain, but I
got confused. "COSTS OFF" is enough.

regards

--
Tomas Vondra
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