Re: Why do we expand tuples in execMain.c?

On 08/08/2018 09:15 PM, Andres Freund wrote:
>
> On August 9, 2018 1:33:17 AM GMT+05:30, Andrew Dunstan <andrew.dunstan@2ndquadrant.com> wrote:
>>
>> On 08/08/2018 12:20 AM, Andres Freund wrote:
>>> Hi,
>>>
>>> I noticed
>>>                 if (HeapTupleHeaderGetNatts(tuple.t_data) <
>>>                     RelationGetDescr(erm->relation)->natts)
>>>                 {
>>>                     copyTuple = heap_expand_tuple(&tuple,
>>>                                                   RelationGetDescr(erm->relation));
>>>                 }
>>>                 else
>>>                 {
>>>                     /* successful, copy tuple */
>>>                     copyTuple = heap_copytuple(&tuple);
>>>                 }
>>>
>>> in EvalPlanQualFetchRowMarks, and I'm somewhat confused why it's
>> there?
>>> If it's required here, why isn't it required in dozens of other
>> places?
>>>
>>
>>
>> Not dozens, I think, since you can't have short records for catalog
>> tables, which account for most of the calls to heap_copytuple().
>>
>> I will look at the remainder of cases (less than 10) and reply in a day
>>
>> or two.
> But why is it needed at all, and the deforming code at the site where we access the columns isn't sufficient?
>


Yeah, I think you're right, and this is vestigial code that I neglected 
to remove when cleaning up from development.

I'll fix it.

cheers

andrew

-- 
Andrew Dunstan                https://www.2ndQuadrant.com
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