Re: Quesion about querying distributed databases

Laurenz Albe <laurenz.albe@cybertec.at>

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: 2025-03-05T07:39:21Z
Lists: pgsql-general
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 for me using FDW.
> 
> The problem here is that it collects all of the product_id values from the ItemCategories table [...]
> 
> That's not scalable. Is there a workaround for this?

Without having scrutinized the case in detail: if your data are organized in an
entity-attribute-value design and distributed across three databases, you cannot
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