On 30 March 2018 at 15:05, Andres Freund <andres@anarazel.de> wrote:
>> + * To allow join removal to happen, we can't reference the CTID column
>> + * of an otherwise-removable relation.
>
> A brief hint why wouldn't hurt.
Maybe something like:
/*
* Join removal is only ever possible when no columns of the
to-be-removed relation
* are referenced. If we added the CTID here then we could
inadvertently disable join
* removal. We'll need to delay adding the CTID until after join
removal takes place.
*/
(I've not read the code, just the thread)
--
David Rowley http://www.2ndQuadrant.com/
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