From: Chao Li <li.evan.chao@gmail.com>
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Subject: Small fixes for CHECKPOINT FLUSH_UNLOGGED
Message-Id: <4855807D-F1CA-44E6-9B58-406691832848@gmail.com>
Date: Mon, 25 May 2026 15:07:38 +0800
Cc: Nathan Bossart <nathandbossart@gmail.com>,
 Christoph Berg <myon@debian.org>
To: PostgreSQL Hackers <pgsql-hackers@lists.postgresql.org>
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 <https://www.postgresql.org/message-id/4855807D-F1CA-44E6-9B58-406691832848%40gmail.com>
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Hi,

I just tested =E2=80=9CAdd FLUSH_UNLOGGED option to CHECKPOINT =
command=E2=80=9D, and found no functional issue. I only noticed a couple =
of small issues.

1. Tab-completion for FLUSH_UNLOGGED misses its boolean value

FLUSH_UNLOGGED can take a boolean value, but tab completion does not =
suggest ON/OFF for it. For comparison, REPACK does:
```
evantest=3D# checkpoint (FLUSH_UNLOGGED o

evantest=3D# repack (concurrently O
OFF ON
```The fix just follows the existing code for REPACK. After the fix:
```
evantest=3D# checkpoint (flush_unlogged O
OFF ON
```

2. The CHECKPOINT doc still says =E2=80=9CAll data files will be flushed =
to disk=E2=80=9D

After introducing FLUSH_UNLOGGED, CHECKPOINT by default no longer =
flushes dirty buffers of unlogged relations, but checkpoint.sgml still =
says =E2=80=9CAll data files will be flushed to disk.=E2=80=9D That =
seems stale, so I updated the doc.

These are two small changes, but to make the patch easier to process, I =
split them into two commits.

Best reagards,
--
Chao Li (Evan)
HighGo Software Co., Ltd.
https://www.highgo.com/


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