Hi,
TL;DR: it works as expected/designed.
Alan>extendedForPrepared to avoid the multiple round trips to the server.
The default setting is a significant performance impact if there is any
meaningful network latency
Would you please elaborate and/or provide a test case for the "performance impact"?
Note: you might want to collect some trace logs (loggerLevel=TRACE&loggerFile=pgjdbc-trace.log) in order to count the roundtrips.
Alan>The fetch size will not be respected with the
preferQueryMode property present
That setting means pgjdbc would use "Simple Query" to execute con.createStatement() kind of statements.
"Simple query" does not support portals, and there is no room to specify "fetch size".
It is just <<'Q' len:Int32 text:string>> message to the server, and it always replies with full set of rows.
In case you absolutely need to use preferQueryMode=extendedForPrepared, you can make fetchsize to work by using con.prepareStatement(...)
Vladimir
