index 21a36a058186637cba460691453d61a533a15305..853c457582903445bf8f6686633085937e9edaaf 100644 (file)
@@ -5,7 +5,7 @@ TODO list for PostgreSQL
Bracketed items "[]" have more detail.
Current maintainer: Bruce Momjian (pgman@candle.pha.pa.us)
-Last updated: Wed Nov 3 22:57:53 EST 2004
+Last updated: Thu Nov 4 11:19:28 EST 2004
The most recent version of this document can be viewed at the PostgreSQL web
site, http://www.PostgreSQL.org.
order. Another method would be to sort heap ctids matching the index
before accessing the heap rows.
-* Allow the creation of bitmap indexes which can be quickly combined
- with other bitmap indexes
+* Allow non-bitmap indexes to be combined by creating bitmaps in memory
Bitmap indexes index single columns that can be combined with other bitmap
indexes to dynamically create a composite index to match a specific query.
Each index is a bitmap, and the bitmaps are bitwise AND'ed or OR'ed to be
- combined. Such indexes could be more compact if there are few unique
- value. Also, perhaps they can be lossy requiring a scan of the heap page
- to find matching rows.
+ combined. They can index by tid or can be lossy requiring a scan of the
+ heap page to find matching rows.
-* Allow non-bitmap indexes to be combined
+* Allow the creation of on-disk bitmap indexes which can be quickly
+ combined with other bitmap indexes
- Do lookups on non-bitmap indexes and create bitmaps in memory that can be
- combined with other indexes.
+ Such indexes could be more compact if there are few unique value.
* Allow use of indexes to search for NULLs