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From: Harald Fuchs <hari.fuchs@gmail.com>
Subject: Re: bad COPY performance with NOTIFY in a trigger
Date: Fri, 05 Feb 2016 09:40:44 +0100
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Tom Lane <tgl@sss.pgh.pa.us> writes:

> No surprise, see AsyncExistsPendingNotify.  You would have a lot of other
> performance issues with sending hundreds of thousands of distinct notify
> events from one transaction anyway, so I can't get terribly excited about
> this.

@Filip: you probably want a per-statement trigger rather than a per-row
trigger: insert all rows with COPY, then send one notification.

You have to mark the new rows somehow yourself; unfortunately PostgreSQL
has no way to tell them in a statement trigger.



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