Message-ID: <gh-pgjdbc-pgjdbc-3483-c2602663731@github.com>
From: "vlsi (@vlsi)" <noreply+vlsi@github.com>
To: "pgjdbc/pgjdbc" <noreply+pgjdbc-pgjdbc@github.com>
Date: Mon, 20 Jan 2025 15:08:28 +0000
Subject: Re: [pgjdbc/pgjdbc] issue #3483: Support adaptive fetching without enforcing memory limits, and/or have a separate buffer size for it
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I've raised a question on the hackers list: https://www.postgresql.org/message-id/CAB%3DJe-HyOz00Ms6pMuOJoCig1eNDp1hpejMvqz%3Dg6M--hoxnKA%40mail.gmail.com

>One would also consider that someone may want to only limit by byte size, and not by row count. For example, maybe you pass 0 rows to [Execute](https://www.postgresql.org/docs/current/protocol-message-formats.html#PROTOCOL-MESSAGE-FORMATS-EXECUTE) but then still request a byte size limit using the proposed mechanism - in this case, PG would fetch as many rows as possible that fit within the byte size limit.

I am afraid it might break the semantics: "execute 0" was supposed to fetch all the rows, and the application might assume extra fetches would not be required after "fetch all rows" execute. So I think it might be ok to keep "fetch all" intact.