Re: Streaming decoding fails with "unexpected table_index_fetch_tuple call during logical decoding" when a relation has a TOASTed conbin (follow-up to BUG #18641)

> On Oct 27, 2026, at 14:42, Hayato Kuroda (Fujitsu) <kuroda(dot)hayato(at)fujitsu(dot)com> wrote:
>
> Hi Peter,
>
>> Since you are refactoring this flag anyway, would it be better to try
>> to eliminate the global-variable completely? e.g. expose the same
>> information by some accessor function.
>>
>> -extern PGDLLIMPORT bool bsysscan;
>> +extern PGDLLIMPORT int sysscan_depth;
>
> Good point, it can be removed by providing few functions. v5 did the same.
> We need to keep bsysscan anyway for back branches, so the patch shape for them
> is slightly different, see v5-PG18.
>
> Best regards,
> Hayato Kuroda
> FUJITSU LIMITED
>
> <v5-0001-Track-the-depth-of-scans-of-system-tables.patch><nocfbot-v5-PG18-0001-Track-the-depth-of-scans-of-system-tables.patch><nocfbot-v5-PG19-0001-Track-the-depth-of-scans-of-system-tables.patch>

Hi Hayato,

I agree with the solution. However, I have a minor concern about the naming. BeginSystemTableScan() and EndSystemTableScan() sound like functions that actually start and end system table scans, whereas they only track sysscan_depth. How about renaming them to TrackSystemTableScanStart() and TrackSystemTableScanEnd() to better reflect their purpose?

Best regards,
--
Chao Li (Evan)
HighGo Software Co., Ltd.
https://www.highgo.com/