From: Matthias Leisi <matthias@leisi.net>
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Subject: Re: Record last SELECT on a row?
Date: Thu, 18 Dec 2025 08:17:12 +0100
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>> If the application's behavior is simple and well-defined, this might
>> be good enough, of course.
>=20
>=20
> FWIW when I read the original email in the thread I got the impression =
that the application behavior was pretty simple WRT this table. But of =
course I could easily be wrong...

You are not wrong. The use case is in fact the `userpref` table used by =
Spamassassin. Left unmaintained, and given a large-enough user base, =
this has the tendency to grow considerably over time, so we want to =
gradually remove entries not actually used any more. (And we don=E2=80=99t=
 want to patch Spamassassin core code to do this by itself=E2=80=A6)

I=E2=80=99ll give it a try with ab/using RLS, which we use for some =
other use cases anyway already.

Thanks a lot for the suggestions in the thread, much appreciated!

=E2=80=94 Matthias


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<html aria-label=3D"message body"><head><meta http-equiv=3D"content-type" =
content=3D"text/html; charset=3Dutf-8"></head><body =
style=3D"overflow-wrap: break-word; -webkit-nbsp-mode: space; =
line-break: after-white-space;"><div><br><blockquote =
type=3D"cite"><div><blockquote type=3D"cite" style=3D"font-family: =
Menlo-Regular; font-size: 11px; font-style: normal; font-variant-caps: =
normal; font-weight: 400; letter-spacing: normal; orphans: auto; =
text-align: start; text-indent: 0px; text-transform: none; white-space: =
normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px; =
text-decoration: none;">If the application's behavior is simple and =
well-defined, this might<br>be good enough, of =
course.<br></blockquote><br style=3D"caret-color: rgb(0, 0, 0); =
font-family: Menlo-Regular; font-size: 11px; font-style: normal; =
font-variant-caps: normal; font-weight: 400; letter-spacing: normal; =
text-align: start; text-indent: 0px; text-transform: none; white-space: =
normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; =
text-decoration: none;"><br style=3D"caret-color: rgb(0, 0, 0); =
font-family: Menlo-Regular; font-size: 11px; font-style: normal; =
font-variant-caps: normal; font-weight: 400; letter-spacing: normal; =
text-align: start; text-indent: 0px; text-transform: none; white-space: =
normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; =
text-decoration: none;"><span style=3D"caret-color: rgb(0, 0, 0); =
font-family: Menlo-Regular; font-size: 11px; font-style: normal; =
font-variant-caps: normal; font-weight: 400; letter-spacing: normal; =
text-align: start; text-indent: 0px; text-transform: none; white-space: =
normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; =
text-decoration: none; float: none; display: inline !important;">FWIW =
when I read the original email in the thread I got the impression that =
the application behavior was pretty simple WRT this table. But of course =
I could easily be wrong...</span><br style=3D"caret-color: rgb(0, 0, 0); =
font-family: Menlo-Regular; font-size: 11px; font-style: normal; =
font-variant-caps: normal; font-weight: 400; letter-spacing: normal; =
text-align: start; text-indent: 0px; text-transform: none; white-space: =
normal; word-spacing: 0px; -webkit-text-stroke-width: 0px; =
text-decoration: none;"></div></blockquote><div><br></div>You are not =
wrong. The use case is in fact the `userpref` table used by =
Spamassassin. Left unmaintained, and given a large-enough user base, =
this has the tendency to grow considerably over time, so we want to =
gradually remove entries not actually used any more. (And we don=E2=80=99t=
 want to patch Spamassassin core code to do this by =
itself=E2=80=A6)</div><div><br></div><div>I=E2=80=99ll give it a try =
with ab/using RLS, which we use for some other use cases anyway =
already.</div><div><br></div><div>Thanks a lot for the suggestions in =
the thread, much appreciated!</div><div><br></div><div>=E2=80=94 =
Matthias</div><div><br></div><div><br></div></body></html>=

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