Re: ATTACH/DETACH PARTITION CONCURRENTLY

On 9 November 2018 at 05:34, Robert Haas <robertmhaas@gmail.com> wrote:
> I suspect the only good way of fixing this problem is using a single
> snapshot to perform both the scan of pg_inherits and the subsequent
> pg_class lookups.  That way, you know that you are seeing the state of
> the whole partitioning hierarchy as it existed at some particular
> point in time -- every commit is either fully reflected in the
> constructed PartitionDesc or not reflected at all.  Unfortunately,
> that would mean that we can't use the syscache to perform the lookups,
> which might have unhappy performance consequences.

I do have a patch sitting around that moves the relpartbound into a
new catalogue table named pg_partition. This gets rid of the usage of
pg_inherits for partitioned tables. I wonder if that problem is easier
to solve with that.  It also solves the issue with long partition keys
and lack of toast table on pg_class.

-- 
 David Rowley                   http://www.2ndQuadrant.com/
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