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From: Ron Johnson <ronljohnsonjr@gmail.com>
Date: Wed, 18 Feb 2026 10:07:22 -0500
Message-ID: <CANzqJaD7mjDcXKNcESLJ+oOd0GDZQvCc45hvGc7LD+zW9COKUg@mail.gmail.com>
Subject: Re: Can we get sha* function over text, that could be used in index?
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On Wed, Feb 18, 2026 at 9:58=E2=80=AFAM hubert depesz lubaczewski <depesz@d=
epesz.com>
wrote:

> Hi,
> So, we have various sha* functions.
>
> And I recently got asked about using them as a based for unique index
> over long texts.
> Normally one would do it with md5(text), but the person asking wanted to
> use sha().


I think I'd push back, asking them if they really need
cryptographically-secure hashing (which they most probably don't).

--=20
Death to <Redacted>, and butter sauce.
Don't boil me, I'm still alive.
<Redacted> lobster!

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<div dir=3D"ltr"><div dir=3D"ltr">On Wed, Feb 18, 2026 at 9:58=E2=80=AFAM h=
ubert depesz lubaczewski &lt;<a href=3D"mailto:depesz@depesz.com">depesz@de=
pesz.com</a>&gt; wrote:</div><div class=3D"gmail_quote gmail_quote_containe=
r"><blockquote class=3D"gmail_quote" style=3D"margin:0px 0px 0px 0.8ex;bord=
er-left:1px solid rgb(204,204,204);padding-left:1ex">Hi,<br>
So, we have various sha* functions.<br>
<br>
And I recently got asked about using them as a based for unique index<br>
over long texts.<br>
Normally one would do it with md5(text), but the person asking wanted to<br=
>
use sha().</blockquote><div></div></div><div><br clear=3D"all"></div><div>I=
 think I&#39;d push back, asking them if they really need cryptographically=
-secure hashing (which they most probably don&#39;t).</div><div><br></div><=
span class=3D"gmail_signature_prefix">-- </span><br><div dir=3D"ltr" class=
=3D"gmail_signature"><div dir=3D"ltr">Death to &lt;Redacted&gt;, and butter=
 sauce.<div>Don&#39;t boil me, I&#39;m still alive.<br><div><div>&lt;Redact=
ed&gt; lobster!</div></div></div></div></div></div>

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