Message-ID: <caf4e99941b3c83bb9eab91e33b144b826b68f79.camel@cybertec.at>
Subject: Re: Quesion about querying distributed databases
From: Laurenz Albe <laurenz.albe@cybertec.at>
To: me nefcanto <sn.1361@gmail.com>, Adrian Klaver
 <adrian.klaver@aklaver.com>
Cc: pgsql-general@lists.postgresql.org
Date: Wed, 05 Mar 2025 08:39:21 +0100
In-Reply-To: <CAEHBEOD969YrbPH_z9OEmThWx3-w4sMMaHLhZLOQwqCwE8Y58Q@mail.gmail.com>
References: 
	<CAEHBEOBuoMFWuhHM3L_Zr6o1enELju-Vns6Pknt4TT+6MFQOwQ@mail.gmail.com>
	 <fd47b28c-8f6b-4bfb-a393-160c5c3de8c0@aklaver.com>
	 <CAEHBEOD969YrbPH_z9OEmThWx3-w4sMMaHLhZLOQwqCwE8Y58Q@mail.gmail.com>
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On Wed, 2025-03-05 at 10:12 +0330, me nefcanto wrote:
> Adrian Klaver, thank you for the link. I asked the AI to create a query f=
or me using FDW.
>=20
> The problem here is that it collects all of the product_id values from th=
e ItemCategories table [...]
>=20
> That's not scalable. Is there a workaround for this?

Without having scrutinized the case in detail: if your data are organized i=
n an
entity-attribute-value design and distributed across three databases, you c=
annot
expect to end up with efficient queries.

Perhaps you can extract the data and load them into a reasonably organized
single database.  Such an ETL process might make the task much easier.

Yours,
Laurenz Albe