On 20/02/18 07:42, Andres Freund wrote:
> Hi,
>
> On 2018-02-17 00:23:40 +0100, Tomas Vondra wrote:
>> Anyway, I consider the performance to be OK. But perhaps Andres could
>> comment on this too, as he requested the benchmarks.
>
> My performance concerns were less about CREATE TABLE related things than
> about analytics workloads or such, where deforming is the primary
> bottleneck. I think it should be ok, but doing a before/after tpc-h of
> scale 5-10 or so wouldn't be a bad thing to verify.
>
The test Tomas is doing is analytical query, it's running sum on the new
fast default column.
He uses create and create-alter names as comparison between when the
table was created with the columns and when the columns were added using
fast default.
--
Petr Jelinek http://www.2ndQuadrant.com/
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