From: Shane Borden <sborden76@gmail.com>
Message-Id: <7BD04D8E-9307-4107-B4D0-4C281390F996@gmail.com>
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Subject: Re: PARALLEL CTAS
Date: Mon, 12 Dec 2022 12:36:11 -0500
In-Reply-To: <1e0484b6-40a6-15a9-9890-0991c8b8c1da@gmail.com>
Cc: pgsql-sql@lists.postgresql.org
To: Rob Sargent <robjsargent@gmail.com>
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I saw this as an option.  Let=E2=80=99s say you have a million row =
table.  If you copy from STDIN, do you have to spool the source table to =
a local file first?  Looking to replace a CTAS thats doing this all =
within SQL statements now.
---

Thanks,


Shane Borden
sborden76@gmail.com

> On Dec 12, 2022, at 12:25 PM, Rob Sargent <robjsargent@gmail.com> =
wrote:
>=20
> On 12/12/22 10:13, Shane Borden wrote:
>> The issue is there are certain performance benefits to be had by =
doing parallel CTAS operations and when converting from Oracle to =
PostgreSQL switching to a =E2=80=9CCOPY=E2=80=9D operation isn=E2=80=99t =
feasible.
>> ---
>>=20
>> Thanks,
>>=20
> Today I suspect you're left with something like the following:
> - CTAS from source where 1=3D2 (i.e. table definition via select =
semantics)
> - copy from stdin (filled with intended CTAS select)
>=20
>=20
>=20


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<html><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;">I saw this as =
an option. &nbsp;Let=E2=80=99s say you have a million row table. =
&nbsp;If you copy from STDIN, do you have to spool the source table to a =
local file first? &nbsp;Looking to replace a CTAS thats doing this all =
within SQL statements now.<br><div>
<div>---<br><br>Thanks,<br><br><br>Shane =
Borden<br>sborden76@gmail.com</div>

</div>
<div><br><blockquote type=3D"cite"><div>On Dec 12, 2022, at 12:25 PM, =
Rob Sargent &lt;robjsargent@gmail.com&gt; wrote:</div><br =
class=3D"Apple-interchange-newline"><div><div>On 12/12/22 10:13, Shane =
Borden wrote:<br><blockquote type=3D"cite">The issue is there are =
certain performance benefits to be had by doing parallel CTAS operations =
and when converting from Oracle to PostgreSQL switching to a =E2=80=9CCOPY=
=E2=80=9D operation isn=E2=80=99t =
feasible.<br>---<br><br>Thanks,<br><br></blockquote>Today I suspect =
you're left with something like the following:<br>- CTAS from source =
where 1=3D2 (i.e. table definition via select semantics)<br>- copy from =
stdin (filled with intended CTAS =
select)<br><br><br><br></div></div></blockquote></div><br></body></html>=

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