On 9/21/07, Tom Lane <[EMAIL PROTECTED]> wrote: > > > so this example is getting past the heuristic tests in > heap_page_prune_opt almost every time. Why is that? Too tired to poke > at it more tonight. > > I guess you already know the answer now, but anyways: Since we are updating a single tuple in a single transaction, each update is preceded by a sequential scan. All but last pages are completely full and marked prunable, so HOT would try to (unsuccessfully) prune every (except may be last) page.
Thanks, Pavan -- Pavan Deolasee EnterpriseDB http://www.enterprisedb.com
