Bruce Momjian <br...@momjian.us> writes:
> On Mon, Jan 11, 2021 at 07:40:18PM +0800, 曾文旌 wrote:
>> This is indeed a typical scenario for a partitioned table.
>> there are two basic operations
>> 1) Monthly DETACH old child table
>> 2) Monthly ATTACH new child table
>>
>> For 1) The DETACH old child table can be finished immediately, global index
>> can be kept valid after DETACH is completed, and the cleanup of garbage data
>> in global index can be deferred to VACUUM.
> Yes, we can keep the index rows for the deleted partition and clean them
> up later, but what is the advantage of partitioning then? Just heap
> deletion quickly? Is that enough of a value?
More to the point, you still have a massive index cleanup operation to do.
Deferred or not, that's going to take a lot of cycles, and it will leave
you with a bloated global index. I find it hard to believe that this
approach will seem like an improvement over doing partitioning the way
we do it now.
regards, tom lane
