Add all heap page rows visible bitmap idea:

<   the heap.  One way to allow this is to set a bit to index tuples
>   the heap.  One way to allow this is to set a bit on index tuples
<   be cleared when a heap tuple is expired.
<
>   be cleared when a heap tuple is expired.  Another idea is to maintain
>   a bitmap of heap pages where all rows are visible to all backends,
>   and allow index lookups to reference that bitmap to avoid heap
>   lookups, perhaps the same bitmap we might add someday to determine
>   which heap pages need vacuuming.

diff --git a/doc/TODO b/doc/TODO
index 22c6e3c4614de55d5af86a5b3c2981c1f1160f72..c3bf43a5f8573525b73f379f0affa101754035ad 100644 (file)
--- a/doc/TODO
+++ b/doc/TODO
@@ -2,7 +2,7 @@
 PostgreSQL TODO List
 ====================
 Current maintainer:    Bruce Momjian ([email protected])
-Last updated:      Thu Dec  1 17:12:27 EST 2005
+Last updated:      Thu Dec  1 17:30:23 EST 2005
 
 The most recent version of this document can be viewed at
 http://www.postgresql.org/docs/faqs.TODO.html.
@@ -859,11 +859,14 @@ Cache Usage
 
   Currently indexes do not have enough tuple visibility information 
   to allow data to be pulled from the index without also accessing 
-  the heap.  One way to allow this is to set a bit to index tuples 
+  the heap.  One way to allow this is to set a bit on index tuples 
   to indicate if a tuple is currently visible to all transactions 
   when the first valid heap lookup happens.  This bit would have to 
-  be cleared when a heap tuple is expired.
-
+  be cleared when a heap tuple is expired.  Another idea is to maintain
+  a bitmap of heap pages where all rows are visible to all backends,
+  and allow index lookups to reference that bitmap to avoid heap
+  lookups, perhaps the same bitmap we might add someday to determine 
+  which heap pages need vacuuming.
 
 * Consider automatic caching of queries at various levels:
 

diff --git a/doc/src/FAQ/TODO.html b/doc/src/FAQ/TODO.html
index 7bb7cd28420c23329a310da42f67ed15118eca1d..7e4961eaa7be943013016adc546d2ac5e8244a58 100644 (file)
--- a/doc/src/FAQ/TODO.html
+++ b/doc/src/FAQ/TODO.html
@@ -8,7 +8,7 @@
 
 PostgreSQL TODO List
 Current maintainer:     Bruce Momjian ([email protected])
-Last updated:           Thu Dec  1 17:12:27 EST 2005
+Last updated:           Thu Dec  1 17:30:23 EST 2005
 
 The most recent version of this document can be viewed at
 http://www.postgresql.org/docs/faqs.TODO.html.
@@ -778,10 +778,14 @@ first.
   Allow data to be pulled directly from indexes
   Currently indexes do not have enough tuple visibility information 
   to allow data to be pulled from the index without also accessing 
-  the heap.  One way to allow this is to set a bit to index tuples 
+  the heap.  One way to allow this is to set a bit on index tuples 
   to indicate if a tuple is currently visible to all transactions 
   when the first valid heap lookup happens.  This bit would have to 
-  be cleared when a heap tuple is expired.
+  be cleared when a heap tuple is expired.  Another idea is to maintain
+  a bitmap of heap pages where all rows are visible to all backends,
+  and allow index lookups to reference that bitmap to avoid heap
+  lookups, perhaps the same bitmap we might add someday to determine 
+  which heap pages need vacuuming.
 
   Consider automatic caching of queries at various levels: