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From: Ron Johnson <ronljohnsonjr@gmail.com>
Date: Mon, 29 Dec 2025 02:21:41 -0500
Message-ID: <CANzqJaBX-SZZcHn71xgqtSKx6ekZGdHPSgCmP2co5=-KDu4Q-Q@mail.gmail.com>
Subject: psql: print values and return the COUNT(*) value to bash?
To: pgsql-general <pgsql-general@postgresql.org>
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Currently I do this in a bash script:
Tbl=table_1
Fld=field_1
Sql="SELECT CURRENT_TIMESTAMP - MIN($Fld) AS days_ago
          , MIN($Fld) as oldest_date
          , COUNT(*) AS cnt
     FROM $Tbl;"
psql -h <host> <db> -Xc "${Sql}"
 days_ago | oldest_date | cnt
----------+-------------+-----
          |             |   0
(1 row)

More stuff happens after this.  I want to print out these four lines, but
also test the COUNT(*) value and bypass other bash commands if the count ==
0.

Is there any relatively simple way to do this (psql print and return
count(*))?

-- 
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>Currently I do this in a bash script:</div><span styl=
e=3D"font-family:monospace">Tbl=3Dtable_1</span><br style=3D"font-family:mo=
nospace"><div><font face=3D"monospace">Fld=3Dfield_1<br>Sql=3D&quot;SELECT =
CURRENT_TIMESTAMP - MIN($Fld) AS days_ago</font></div><div><font face=3D"mo=
nospace">=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 , MIN($Fld) as oldest_date</fon=
t></div><div><font face=3D"monospace">=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 , =
COUNT(*) AS cnt=C2=A0</font></div><div><font face=3D"monospace">=C2=A0 =C2=
=A0 =C2=A0FROM $Tbl;&quot;<br>psql -h &lt;host&gt; &lt;db&gt; -Xc &quot;${S=
ql}&quot;</font></div><div><span style=3D"font-family:monospace">=C2=A0days=
_ago | oldest_date | cnt</span></div><div><font face=3D"monospace">--------=
--+-------------+-----<br>=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 | =C2=A0 =C2=
=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 | =C2=A0 0<br>(1 row)<br></font></div><div>=
<br></div><div>More stuff happens after this.=C2=A0 I want to print out the=
se four lines, but also test the <font face=3D"monospace">COUNT(*)</font> v=
alue and bypass other bash commands if the count =3D=3D 0.</div><div><br></=
div><div>Is there any relatively simple way to=C2=A0do this (psql print and=
 return count(*))?</div><div><br></div><span class=3D"gmail_signature_prefi=
x">-- </span><br><div dir=3D"ltr" class=3D"gmail_signature" data-smartmail=
=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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