From: Bruce Momjian Date: Wed, 15 Aug 2007 15:53:30 +0000 (+0000) Subject: Add third idea about pulling data from indexes. X-Git-Tag: REL9_0_0~5203 X-Git-Url: http://git.osdn.net/view?a=commitdiff_plain;h=5ff95e6b8e19cef5e7fd15368194da1d29ebb0be;p=pg-rex%2Fsyncrep.git Add third idea about pulling data from indexes. > A third idea would be for a heap scan to check if all rows are visible > and if so set a per-table flag which can be checked by index scans. > Any change to the table would have to clear the flag. To detect > changes during the heap scan a counter could be set at the start and > checked at the end --- if it is the same, the table has not been > modified --- any table change would increment the counter. --- diff --git a/doc/src/FAQ/TODO.html b/doc/src/FAQ/TODO.html index 076431b275..35ee8b0593 100644 --- a/doc/src/FAQ/TODO.html +++ b/doc/src/FAQ/TODO.html @@ -8,7 +8,7 @@

PostgreSQL TODO List

Current maintainer: Bruce Momjian (bruce@momjian.us)
-Last updated: Wed Aug 15 11:36:16 EDT 2007 +Last updated: Wed Aug 15 11:48:07 EDT 2007

The most recent version of this document can be viewed at
http://www.postgresql.org/docs/faqs.TODO.html. @@ -1011,6 +1011,13 @@ first. There is also a developer's wiki at
accessed bitmaps would have to be stored in shared memory. One 8k page of bitmaps could track 512MB of heap pages.

+

A third idea would be for a heap scan to check if all rows are visible + and if so set a per-table flag which can be checked by index scans. + Any change to the table would have to clear the flag. To detect + changes during the heap scan a counter could be set at the start and + checked at the end --- if it is the same, the table has not been + modified --- any table change would increment the counter. +

  • Consider automatic caching of statements at various levels: