Re: Making "COPY partitioned_table FROM" faster

On Mon, Jul 30, 2018 at 11:21 AM, Peter Eisentraut <
peter(dot)eisentraut(at)2ndquadrant(dot)com> wrote:

> On 30/07/2018 15:26, David Rowley wrote:
> >> - Add some tests. The if (nBufferedTuples > 0) that flushes the tuples
> >> when the partition changes is not currently exercised.
> >
> > That seems like a good idea. In fact, it uncovered a bug around
> > ConvertPartitionTupleSlot() freeing the previously stored tuple out
> > the slot which resulted in a crash. I didn't notice before because my
> > test had previously not required any tuple conversions.
>
> I think we need to think of a better place to put that temporary file,
> and clean it up properly afterwards. I'm not sure whether we have
> existing uses like that.
>
> Also, maybe the test should check afterwards that the right count of
> rows ended up in each partition?
>
> Yea, I actually would suggest changing the data inserted in the third
insert statement to have 'Three' in the third column:
insert into parted_copytest select x,1,'One' from
generate_series(1011,1020) x;
And then this check:
select count(*) from parted_copytest group by a, b, c;