From: Tom Lane <tgl@sss.pgh.pa.us>
To: Richard Guo <guofenglinux@gmail.com>
cc: pgsql-hackers@lists.postgresql.org
Subject: Re: Allowing parallel-safe initplans
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Comments: In-reply-to Richard Guo <guofenglinux@gmail.com>
	message dated "Thu, 13 Apr 2023 16:23:06 +0800"
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Date: Thu, 13 Apr 2023 10:00:51 -0400
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Richard Guo <guofenglinux@gmail.com> writes:
> * For the diff in standard_planner, I was wondering why not move the
> initPlans up to the Gather node, just as we did before.  So I tried that
> way but did not notice the breakage of regression tests as stated in the
> comments.  Would you please confirm that?

Try it with debug_parallel_query = regress.

> * Not related to this patch.  In SS_make_initplan_from_plan, the comment
> says that the node's parParam and args lists remain empty.  I wonder if
> we need to explicitly set node->parParam and node->args to NIL before
> that comment, or can we depend on makeNode to initialize them to NIL?

I'm generally a fan of explicitly initializing fields, but the basic
argument for that is greppability.  That comment serves the purpose,
so I don't feel a big need to change it.

			regards, tom lane