Re: Partitionning: support for Truncate Table WHERE

On 2016/12/07 15:26, Craig Ringer wrote:
> On 7 December 2016 at 07:29, legrand legrand
> <legrand_legrand@hotmail.com> wrote:
> 
>> Working in a DSS environment, we often need to truncate table partitions
>> regarding a WHERE condition and have to
>> [...]
>> Would be pleased to ear your feedback regarding this.
> 
> It sounds like something that'd be useful to do on top of declarative
> partitioning, once that is merged. Perhaps you could start by reading
> and testing the declarative partitioning patch. That'll give you a
> better idea of the practicalities of doing what you propose on top of
> it, and give you an opportunity to suggest changes to the declarative
> partitioning scheme that might make conditional truncate easier later.

Agreed.

If I understand the request correctly, TRUNCATE on the parent table (a
partitioned table), which currently recurses to *all* child tables
(partitions), should have a restricting WHERE clause, right?  It would
become possible to implement something like that with the new declarative
partitioned tables.  As Crag mentioned, you can take a look at the
discussion about declarative partitioning in the emails linked to at the
following page: https://commitfest.postgresql.org/12/611/

Thanks,
Amit