On Monday, June 20, 2016, John R Pierce <
pierce@hogranch.com> wrote:
On 6/20/2016 8:03 AM, Scott Mead wrote:
I believe that free space is only available to UPDATE, not INSERT.
incorrect. in fact, an update is performed identically to an INSERT + DELETE(old)
Except for heap-only-tuple optimization, right? We cannot build a HOT chain if the user requests a delete separately since their is no longer an association to trace from the old record.
I suspect this affects free space usage to some degree as well but I agree and believe that the reclaimed space is not forbidden to be used (I wouldn't rely on my word though and haven't tried to find relevant documentation).
David J.