Hi Alvaro, On 2019/04/03 21:01, Alvaro Herrera wrote: > On 2019-Apr-03, Kyotaro HORIGUCHI wrote: > >> Hello. >> >> At Wed, 3 Apr 2019 12:55:06 +0900, Amit Langote >> <langote_amit...@lab.ntt.co.jp> wrote in >> <ee892049-0fe4-afe6-cbbf-31cf44fa8...@lab.ntt.co.jp> >>> On 2019/04/03 12:02, Kyotaro HORIGUCHI wrote: >>>> \dPn doesn't show children because the are of 'r' relkind. And >>>> \dPn * doesn't show type for children. >> ... >>> I think it's intentional that leaf partitions are not shown, because the >>> patch is meant to allow showing only the "partitioned" members of >>> partition trees. Regular \d[t|i][+] shows normal tables ('r', 'i', etc.) >>> including their size, but it's useless for partitioned tables ('P', 'I', >>> etc.) as far as showing the size is concerned, so the patch. Even \dPn is >>> meant to only show partitions that are themselves partitioned; note the >>> "P" in the command. >> >> + If the modifier <literal>n</literal> (<quote>nested</quote>) is >> used, >> + then non-root partitioned tables are included, and a column is shown >> + displaying the parent of each partitioned relation. >> >> Ah. I see. "non-root *partitined* tables". I misread the >> phrase. Sorry for the noise. > > Well, is this decision an excellent one, from a UI perspective? I was > surprised by this too and think this should be reconsidered. > > I would opt for having \d NOT show partitions at all, myself.
Hmm, in the previous long discussions on this topic, people were opposed [1] to an idea like this, but maybe they are no longer. Note that the main opposition came to the idea that \d+ would perform simple pg_relation_size for regular tables and something else for partitioned tables, such as, aggregation query over pg_partition_tree. > When you > have many partitions (and we're now making the system scale into the > thousands for a single partitioned table), they clutter the output > making it unusable. So, rather than think as \dP as "the way to show > the aggregate size of a partitioned table or index", I'd think it as > "the way to show detailed info about a partitioned table or index". > Which includes things like displaying its list of partitions and the > size of each. That might be a good idea, but maybe there isn't time left to revise the proposed patch like that for 12? Thanks, Amit [1] https://www.postgresql.org/message-id/flat/495cec7e-f8d9-7e13-4807-90dbf4eec...@lab.ntt.co.jp