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Subject: Re: Making jsonb_agg() faster
From: Chao Li <li.evan.chao@gmail.com>
In-Reply-To: <1985954.1764976473@sss.pgh.pa.us>
Date: Sat, 6 Dec 2025 09:35:51 +0800
Cc: jian he <jian.universality@gmail.com>,
 pgsql-hackers@lists.postgresql.org
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To: Tom Lane <tgl@sss.pgh.pa.us>
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> On Dec 6, 2025, at 07:14, Tom Lane <tgl@sss.pgh.pa.us> wrote:
>=20
> v5, rebased over a couple of recent patches.  No substantive changes.
>=20
> I'd kind of like to get this pushed soon, because it keeps getting
> sideswiped ... does anyone have further comments?

Actually I traced v4 again this week. I tried to find out something to =
comment, but ended up I didn=E2=80=99t find anything significant.

My only nit commit is still about the hard-coded 12:
```
+				case TIMETZOID:
+					/* pass-by-reference */
+					oldcontext =3D =
MemoryContextSwitchTo(outcontext);
+					v->val.datetime.value =3D =
datumCopy(v->val.datetime.value,
+										=
			  false, 12);
```

I commented this before and you explained. But I still think it may =
deserve a comment for why 12 is here, otherwise future reader may also =
get the same confusion as when I first time read this code.

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