| From: | Noah Misch <noah(at)leadboat(dot)com> |
|---|---|
| To: | Marco Nenciarini <marco(dot)nenciarini(at)2ndQuadrant(dot)it> |
| Cc: | pgsql-hackers(at)postgresql(dot)org |
| Subject: | Re: [PATCH] Support for foreign keys with arrays |
| Date: | 2012-03-20 05:07:52 |
| Message-ID: | 20120320050752.GA11554@tornado.leadboat.com |
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| Thread: | |
| Lists: | pgsql-hackers |
On Mon, Mar 19, 2012 at 06:41:39PM +0100, Marco Nenciarini wrote:
> Attached is v5, which should address all the remaining issues.
Looks clean to me.
> On Fri, Mar 16, 2012 at 11:33:12PM -0400, Noah Misch wrote:
> > If the cost doesn't exceed O(F log P), where F is the size of the FK table and
> > P is the size of the PK table, I'm not worried. If it can be O(F^2), we would
> > have a problem to be documented, if not fixed.
>
> We have rewritten the old query in a simpler way; now its cost is O(F log P).
> Here F must represent the size of the "flattened" table, that is, the total
> number of values that must be checked, which seems a reasonable assumption
> in any case.
Great; I find that approach easier to reason about.
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