ERROR: deadlock detected

We saw the following message in the file postgres-serverlog.error:

2023-01-24 17:16:16.578 CET [17468] ERROR: deadlock detected
2023-01-24 17:16:16.578 CET [17468] DETAIL: Process 17468 waits for ShareLock on transaction 90776649; blocked by process 17724.
Process 17724 waits for ShareLock on transaction 90776650; blocked by process 17468.
Process 17468: fetch hc_d03geb
Process 17724: fetch hc_d02ben
2023-01-24 17:16:16.578 CET [17468] HINT: See server log for query details.
2023-01-24 17:16:16.578 CET [17468] CONTEXT: while locking tuple (948,45) in relation "d03geb"
2023-01-24 17:16:16.578 CET [17468] STATEMENT: fetch hc_d03geb

There are no messages in the serverlog itself and in our application
log files. What can we do to get to more information (may be next time)?

The process numbers are internal ones of the PostgreSQL server and not
the Linux PID, correct?

Thanks

matthias
--
Matthias Apitz, ✉ guru(at)unixarea(dot)de, http://www.unixarea.de/ +49-176-38902045
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