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From: "vlsi (@vlsi)" <noreply+vlsi@github.com>
To: "pgjdbc/pgjdbc" <noreply+pgjdbc-pgjdbc@github.com>
Date: Sat, 20 Sep 2025 06:25:07 +0000
Subject: Re: [pgjdbc/pgjdbc] issue #3811: PreparedStatement batch performance issue in a loop on v42.7.6 or later
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@leandrokemp , Previously, `ps.toString();` rendered only the the last value, and 0a88ea425e86dce691a96d6aa7023c20ac887b98 probably fixed it, so now `ps.toString()` renders all the values in a batch. Now `ps.toString()` properly displays all the values it is about to send to the database, and it is far `toString()` to take longer time as the list of values grows. This makes `ps.toString(); ps.addBatch()` loop behave with O(N^2) properties, thus it effectively hangs.

If you want to log the executed statement, you'd better move the logging out of the loop just before `executeBatch`.

I am leaning towards to closing the issue with "working as expected, won't fix" resolution unless you justify the business case behind calling `ps.toString(); ps.addBatch();` within a loop.