On Tue, Jun 30, 2020 at 2:54 PM Amit Langote <amitlangot...@gmail.com> wrote: > On Tue, Jun 30, 2020 at 1:22 PM Ashutosh Bapat > <ashutosh.ba...@2ndquadrant.com> wrote: > > On Tue, 30 Jun 2020 at 08:47, Etsuro Fujita <etsuro.fuj...@gmail.com> wrote: > >> On Mon, Jun 29, 2020 at 7:52 PM Ashutosh Bapat > >> <ashutosh.bapat....@gmail.com> wrote: > >> > On Sun, Jun 28, 2020 at 8:40 PM Tomas Vondra > >> > <tomas.von...@2ndquadrant.com> wrote: > >> > >> > > 3) What about the other DML operations (DELETE/UPDATE)? > >> > > > >> > > The other DML operations could probably benefit from the batching too. > >> > > INSERT was good enough for a PoC, but having batching only for INSERT > >> > > seems somewhat asmymetric. DELETE/UPDATE seem more complicated because > >> > > of quals, but likely doable. > >> > > >> > Bulk INSERTs are more common in a sharded environment because of data > >> > load in say OLAP systems. Bulk update/delete are rare, although not > >> > that rare. So if an approach just supports bulk insert and not bulk > >> > UPDATE/DELETE that will address a large number of usecases IMO. But if > >> > we can make everything work together that would be good as well. > >> > >> In most cases, I think the entire UPDATE/DELETE operations would be > >> pushed down to the remote side by DirectModify. So, I'm not sure we > >> really need the bulk UPDATE/DELETE. > > That may not be true for a partitioned table whose partitions are foreign > > tables. Esp. given the work that Amit Langote is doing [1]. It really > > depends on the ability of postgres_fdw to detect that the DML modifying > > each of the partitions can be pushed down. That may not come easily. > > While it's true that how to accommodate the DirectModify API in the > new inherited update/delete planning approach is an open question on > that thread, I would eventually like to find an answer to that. That > is, that work shouldn't result in losing the foreign partition's > ability to use DirectModify API to optimize updates/deletes.
That would be great! Best regards, Etsuro Fujita
