Re: Another FK violation when referencing a multi-level partitioned table

On 2020-Feb-06, Jehan-Guillaume de Rorthais wrote:

Hello,

> When working on the patch to fix another FK violation [1], I found that FK
> constraints were not properly cloned to partition not directly hooked to the
> root table.

Uh.

> Surprisingly, the comment explains how this should be done in two steps, but
> the code corrupted the first step by skipping inherited constraints and lacks
> the second step:
> 
>      * [...]to avoid duplicates.  So do it in two
>      * steps: first construct the list of constraints to clone, then go over
>      * that list cloning those whose parents are not in the list.  (We must
>      * not rely on the parent being seen first, since the catalog scan could
>      * return children first.)
>      */

Strange that this escaped testing previously.

> Please, find in attachment a proposal patch to fix this FK violation.

You fix looks correct to me, so pushed.  I took a minute to apply some
minor corrections to the comments, too.

Thanks for reporting!

-- 
Álvaro Herrera                https://www.2ndQuadrant.com/
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