Re: explain analyze rows=%.0f

On Thu, Jun 23, 2022 at 2:25 AM Ibrar Ahmed <ibrar.ahmad@gmail.com> wrote:
>
> On Thu, Jun 23, 2022 at 1:04 AM David G. Johnston <david.g.johnston@gmail.com> wrote:
>>
>> - WRITE_FLOAT_FIELD(rows, "%.0f");
>> + WRITE_FLOAT_FIELD(rows, "%.2f");
>>
>> This one looks suspicious, though I haven't dug into the code to see exactly what all is being touched.  That it doesn't have an nloops condition like everything else stands out.
>>
> I was also thinking about that, but I don't see any harm when we ultimately truncating that decimal
> at a latter stage of code in case of loop = 1.
>

That change is in the path node which we anyway not going to target as
part of this change. We only want to change the display for actual
rows in Explain Analyze. So, I can't see how the quoted change can
help in any way.

Few miscellaneous comments:
========================
*
 static FullTransactionId XactTopFullTransactionId = {InvalidTransactionId};
-static int nParallelCurrentXids = 0;
+static int nParallelCurrentXids = 0;

I don't see why this change is required.

* Can you please add a comment explaining why we are making this
change for actual rows?

* Can you please write a test case unless there is some existing test
that covers the change by displaying actual rows values in decimal but
in that case patch should have that changed output test? If you don't
think we can reliably write such a test then please let me know the
reason?

-- 
With Regards,
Amit Kapila.