>
> Never, unless you drop and recreate the table. Removing a dropped
> column would change the attnums of following columns, which we
> can't support because the tableoid+attnum is the only persistent
> identifier of a column.
>
> (From memory, operations like VACUUM FULL and CLUSTER will rewri
Ravi Krishna writes:
>> VACUUM would not change the state of the dropped columns.
> When does it change?
Never, unless you drop and recreate the table. Removing a dropped
column would change the attnums of following columns, which we
can't support because the tableoid+attnum is the only persist
>> Just to confirm, we are talking about tables from where some cols were
>> deleted in the past, but
>> VACUUM FULL not run on that table, right ?
>
> VACUUM would not change the state of the dropped columns.
>
When does it change?
Ravi Krishna writes:
>> On Nov 3, 2019, at 11:03 PM, Steve Baldwin wrote:
>> Thanks very much for the explanation Tom !! You are correct - there are
>> dropped columns in the original.
> Just to confirm, we are talking about tables from where some cols were
> deleted in the past, but
> VACUU
> On Nov 3, 2019, at 11:03 PM, Steve Baldwin wrote:
>
> Thanks very much for the explanation Tom !! You are correct - there are
> dropped columns in the original.
Just to confirm, we are talking about tables from where some cols were deleted
in the past, but
VACUUM FULL not run on that ta
Thanks very much for the explanation Tom !! You are correct - there are
dropped columns in the original.
Cheers,
Steve
On Mon, Nov 4, 2019 at 3:01 PM Tom Lane wrote:
> Steve Baldwin writes:
> > I guess the difference doesn't have a huge bearing (as far as I can tell)
> > on the result, but i
Steve Baldwin writes:
> I guess the difference doesn't have a huge bearing (as far as I can tell)
> on the result, but it just seems odd that the inner-most 'Output' step
> outputs the entire row in the case of the copy and only the required field
> in the case of the original table. What triggers
Can someone please help me understand this:
b2bc_dev=# *vacuum full analyze invoice;*
VACUUM
Time: 39.671 ms
b2bc_dev=# *create table invoice_copy as select * from invoice;*
SELECT 23
Time: 11.557 ms
b2bc_dev=# *alter table invoice_copy add primary key (id);*
ALTER TABLE
Time: 9.257 ms
b2bc_dev=#
