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Date: Thu, 6 Mar 2025 10:17:55 +0200
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Subject: Re: Quesion about querying distributed databases
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From: Achilleas Mantzios - cloud <a.mantzios@cloud.gatewaynet.com>
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On 3/5/25 11:55, Laurenz Albe wrote:
> On Wed, 2025-03-05 at 12:57 +0330, me nefcanto wrote:
>> Right now this data is in MariaDB, on separate databases (schema) but on one
>> server. The solution in this situation is to have a cross-database query.
>> (this is the status quo of our application)
>>
>> Now our team has decided to migrate to Postgres. However, we realized that
>> Postgres does not support cross-database queries. And if we want to do so,
>> we should use FDW. So, we thought we might as well put databases on separate
>> servers for scalability if we have to write more code. That's the reason
>> behind this question.
> In MySQL, the terms "database" and "schema" are used for the same thing.
> Not so in PostgreSQL.  I think you should migrate the data into different
> schemas in a single database, pretty much like you had it in MySQL.
> Then you don't need a foreign data wrapper, and I bet the query can
> perform as well as it did on MySQL.
Same thing in MS SQL, as of version 2017 or so.
>
> Yours,
> Laurenz Albe
>
>
>