Re: UPDATE using sub selects

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NikhilS wrote:
> Hi,
>
> As per discussion on -hackers, a patch which allows updates to use
> subselects is attached with this mail.
>
> As per discussion with Tom, I have adopted the following approach:
>
> * Introduce ROWEXPR_SUBLINK type for subqueries that allows multiple column
> outputs.
> * Populate the targetList with PARAM_SUBLINK entries dependent on the
> subselects.
> * Modify the targets in-place into PARAM_EXEC entries in the make_subplan
> phase.
>
> The above does not require any kluges in the targetList processing code path
> at all.
>
> UPDATEs seem to work fine using subselects with this patch. I have modified
> the update.sql regression test to include possible variations .
>
> No documentation changes are present in this patch.
> Feedback, comments appreciated.
>
> Regards,
> Nikhils
> --
> EnterpriseDB               http://www.enterprisedb.com

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  Bruce Momjian  <bruce@momjian.us>          http://momjian.us
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