Horton

Re: Incremental sort for access method with ordered scan support (amcanorderbyop)

Miroslav Bendik <miroslav.bendik@gmail.com>

View thread View on postgr.es
From: Miroslav Bendik <miroslav.bendik@gmail.com>
To: David Rowley <dgrowleyml@gmail.com>
Cc: Richard Guo <guofenglinux@gmail.com>, pgsql-hackers@postgresql.org
Date: 2023-04-19T04:52:59Z
Lists: pgsql-hackers

Attachments

Thanks for feedback

> 2. You can use list_copy_head(root->query_pathkeys,
> list_length(orderbyclauses)); instead of:
>
> + useful_pathkeys = list_truncate(list_copy(root->query_pathkeys),
> +     list_length(orderbyclauses));

This code will crash if query_pathkeys is NIL. I need either modify
list_copy_head (v3.1) or add checks before call (v3.2).

I don't know if it's a good idea to modify list_copy_head. It will add
additional overhead to every call.

-- 
Best regards
Miroslav

Commits

  1. Allow Incremental Sorts on GiST and SP-GiST indexes

  2. Fix list_copy_head() with empty Lists