Thread: BUG #18975: PostgreSQL server doesn't process SQL request correctly over Windows replica of Linux server

The following bug has been logged on the website:

Bug reference:      18975
Logged by:          Egor Chashchin
Email address:      iqcook@gmail.com
PostgreSQL version: 17.5
Operating system:   LInux / Wiondows
Description:

We have next configuration -  master server on Linux Ubuntu and physical
replica on Windows 10 machine. Some kind of simple SELECT SQL request
returns none called on replica - and work correctly on server itself or
Linux physical replica. If we inspect data in windows replica tables - we
see, that all data needed presented.
we captured example of this behavior on this video
https://www.dropbox.com/scl/fi/c8msver0gm78turk3wfsv/2025-07-02_00-14-31.mp4?rlkey=24rhvs9ytroznxyt86xivlxef
Linux - 17.5.1
Windows - 17.5.2
We have this problem with 16.8.x too.
It occurs not with all requests of such kind even on same table, but not
randomly - running same code fails in same place everytime.
Additional attempts were captured too
https://www.dropbox.com/scl/fi/g9h3r7v3gu59j5max9r7k/2025-07-02_00-59-02.mp4?rlkey=0yygbv62hloay32sgapglwrsa

On Tue, 2025-07-01 at 23:10 +0000, PG Bug reporting form wrote:
> PostgreSQL version: 17.5
> Operating system:   LInux / Wiondows
> Description:       
>
> We have next configuration -  master server on Linux Ubuntu and physical
> replica on Windows 10 machine. Some kind of simple SELECT SQL request
> returns none called on replica - and work correctly on server itself or
> Linux physical replica. If we inspect data in windows replica tables - we
> see, that all data needed presented.

That's very likely because the collations differ on both machines, so
the indexes on the standby are corrupted.  You cannot do streaming
replication between Windows and Linux.  Consider using logical replication.

This is unpleasant, but not a bug.

Yours,
Laurenz Albe