Re: ALTER TABLE ADD COLUMN fast default

[Andrew Dunstan]

> On Mar 14, 2018, at 10:58 AM, David Rowley <david.row...@2ndquadrant.com> 
> wrote:
> 
> On 14 March 2018 at 11:36, Andrew Dunstan
> <andrew.duns...@2ndquadrant.com> wrote:
>> Here are the benchmark results from the v15 patch. Fairly similar to
>> previous results. I'm going to run some profiling again to see if I
>> can identify any glaring hotspots. I do suspect that the "physical
>> tlist" optimization sometimes turns out not to be one. It seems
>> perverse to be able to improve a query's performance by dropping a
>> column.
> 
> Can you explain what "fdnmiss" is that appears in the results?
> 
> 

It’s the patched code run against a materialized version of the table, i.e. one 
with no missing attributes.

Cheers

Andrew