Centuries ago, Nostradamus foresaw when ZeugswetterA@spardat.at ("Zeugswetter Andreas DCP SD") would write:
>> > But what about index clearing? When do you scan each index?
>>
>> At the end of each iteration (or earlier, depending on
>> maintenance_work_mem). So for each iteration you would need
>> to scan the indexes.
>>
>> Maybe we could make maintenance_work_mem be the deciding
>> factor; after scanning the indexes, do the release/reacquire
>> locks cycle.
>
> But you could do the indexes first and remember how far you can
> vacuum the heap later.
But the indexes _can't_ be done first; you _first_ need to know which
tuples are dead, which requires looking at the table itself.
--
select 'cbbrowne' || '@' || 'gmail.com';
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