On 27 February 2017 at 10:12, Amit Langote
<Langote_Amit_f8@lab.ntt.co.jp> wrote:
> I agree that my patch failed to de-emphasize the old partitioning method
> enough. The examples in 5.11 Partitioning chapter also did not highlight
> the new partitioning feature as much as it should have been, so it indeed
> reads like a description of how to avoid using the new partitioning
> feature.
Your patch was incredibly useful; I just wanted it earlier.
I think we're probably all agreed that we should highlight benefits of
the new approach more, though the list of caveats should stay
somewhere, just as we did for the original inheritance feature, and
other things such as replication.
> Should we completely remove details about the older partitioning
> methods?
No, because there is much code out there using it for last 12 years
that needs to be explained and there are still some use cases where it
is useful that aren't on the roadmap for partitioning.
> I like the idea of merging what are now two chapters into one and call it
> Partitioned Tables, retaining the text that describes concepts
+1
...but how?
5.10 Partitioned Tables and Related Solutions
5.10.1 Declarative Partitioning (this new feature)
5.10.2 Managing Partitions using Inheritance
5.10.3 Managing Partitions using Union All Views
5.10.4 Accessing tables using BRIN indexes
So first and foremost we highlight the new feature and explain all its
strengths with examples.
We then explain the other possible ways of implementing something
similar. This allows us to explain how to handle cases such as when
partitions have different set of columns etc..
I'm happy to put my name down to write the sections on Union All
Views, which is useful but only mentioned in passing, and the section
on BRIN indexes, all of which would have their own independent sets of
caveats.
--
Simon Riggs http://www.2ndQuadrant.com/
PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services
