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Date: Fri, 1 Nov 2024 21:47:37 +0100 (GMT+01:00)
From: Thiemo Kellner <thiemo@gelassene-pferde.biz>
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Subject: Re: Plans for partitioning of inheriting tables
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It looks to me basically to be a "create table A as select * from B where f=
alse".

01.11.2024 20:38:15 Adrian Klaver <adrian.klaver@aklaver.com>:

> On 11/1/24 12:16, thiemo@gelassene-pferde.biz wrote:
>> Thanks, I shall have a look into it. I was under the assumption the the =
create table like would create no more than a structural copy.
>=20
> Not sure what you mean by structural copy, but the table created by CREAT=
E TABLE LIKE will not have any association with the table it was created fr=
om.
>=20
> https://www.postgresql.org/docs/current/sql-createtable.html
>=20
> "Unlike INHERITS, the new table and original table are completely decoupl=
ed after creation is complete. Changes to the original table will not be ap=
plied to the new table, and it is not possible to include data of the new t=
able in scans of the original table."
>=20
>> Torsten F=C3=B6rtsch <tfoertsch123@gmail.com <mailto:tfoertsch123@gmail.=
com>> escribi=C3=B3:
>> Thiemo,
>>> it looks to me like you are using inheritance just to make sure your SO=
URCES and TOPO_FILES tables have some common columns. If you are not actual=
ly querying the TEMPLATE_TECH table and expect to see all the rows from the=
 other 2 tables in that one table combined, then you could use CREATE TABLE=
 (LIKE ...) instead of inheritance. That way your "child" tables would beco=
me normal tables and you could use declarative partitioning on them.
>>> Even if you are querying the TEMPLATE_TECH table, you could still do th=
at by turning the TEMPLATE_TECH table into a view which performs a UNION AL=
L over the other tables.
>>=20
>=20
> --=20
> Adrian Klaver
> adrian.klaver@aklaver.com