On 2018-Dec-05, Michael Paquier wrote:
> This has been mentioned on the thread where pg_partition_tree has been
> discussed:
> https://www.postgresql.org/message-id/6baeb45a-6222-6b88-342d-37fc7d3cf89a%40lab.ntt.co.jp
>
> It got shaved from the final patch for simplicity as we had enough
> issues to deal with first. Adding a pg_partition_root or a new column
> in pg_partition_tree makes sense. My guts are telling me that a
> separate function is more instinctive to use.
I agree with your guts ... you can combine them (the functions, not the
guts) to obtain the full view of the partition hierarchy just by
applying pg_partition_root() to the argument of pg_partition_tree.
I think with pg_partition_root we can rewrite the FK queries to avoid
WITH RECURSIVE with pg12 servers, but of course with a pg11 server we'll
have to keep using WITH RECURSIVE.
--
Álvaro Herrera https://www.2ndQuadrant.com/
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