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From: Tobias McNulty <tobias@caktusgroup.com>
Date: Sun, 23 Feb 2025 10:34:25 -0500
Message-ID: <CAMGFDKQbLxahN8mthNU47r8iRB67261SQdk+BtbiBuOqtXNrUg@mail.gmail.com>
Subject: Re: documentation question regarding REFRESH MATERIALIZED VIEW CONCURRENTLY
To: Greg Sabino Mullane <htamfids@gmail.com>
Cc: pgsql-general@lists.postgresql.org
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On Sun, Feb 23, 2025 at 10:21=E2=80=AFAM Greg Sabino Mullane <htamfids@gmai=
l.com> wrote:
> This is the correct interpretation. A regular refresh simply runs the que=
ry and replaces the old view, regardless of the number of rows that have ch=
anged. A concurrent refresh runs the query and updates the rows in place, s=
o it is very sensitive as to how many of those rows have changed. This also=
 means that many concurrent refreshes can lead to table bloat. And it will =
generate more WAL than a regular refresh.
>
> My takeaway: use regular refresh when you can. Switch to concurrent if th=
e number of changes is very small, or if constant client access to the view=
 is very important.

This makes sense to me. Many thanks.

Cheers,
Tobias