2018-06-20 10:03 GMT+02:00 Amit Langote <langote_amit...@lab.ntt.co.jp>:
> On 2018/06/20 16:50, Pavel Stehule wrote: > > 2018-06-20 9:44 GMT+02:00 Amit Langote <langote_amit...@lab.ntt.co.jp>: > >> Do you mean \dt continues to show size 0 for partitioned tables, but > with > >> the new option (\dtP+) shows the actual size by aggregating across > >> partitions? +1 to such a feature, but we need to agree on an acceptable > >> implementation for that. How does the aggregation happen: > >> > > > > yes - my proposal is no change for \dt for now. I think so we will have > to > > change it, when partitioning will be more common and number of partitions > > will be high. But it is not today. > > > > \dtP shows only partitions tables (like \dtS shows only system tables), > > with "+" shows sum of all related partitions. > > Ah, okay. That makes sense. > > >> 1. In a new dedicated function in the backend (parallel to > pg_table_size)? > >> > >> or > >> > >> 2. psql issues a separate query to compute the total size of a partition > >> tree > >> > > > > In this moment we can simply do sum on client side, so it is related to > @2. > > I see, okay. > > >> For option 2, I had posted a patch that simplifies writing such a query > >> and posted that here: > >> > >> https://www.postgresql.org/message-id/7a9c5328-5328-52a3- > >> 2a3d-bf1434b4dd1d%40lab.ntt.co.jp > >> > >> With that patch, the query to get the total size of a partition tree > >> becomes as simple as: > >> > >> select sum(pg_table_size(p)) as size > >> from pg_get_inheritance_tables('partitioned_table_name') p > >> > > > > good to know it. Thank you. Do you think so your patch should be included > > to this feature or will be processed independently? > > It seems that it would be useful on its own, as people may want to do > various things once we provide them pg_get_inheritance_table. > ok I'll prepare patch and I'll do note about dependency on your patch. Regards Pavel > Thanks, > Amit > >
