diff --git a/doc/TODO b/doc/TODO index 506db4e5c3..21a36a0581 100644 --- a/doc/TODO +++ b/doc/TODO @@ -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 17:20:38 EST 2004 +Last updated: Wed Nov 3 22:57:53 EST 2004 The most recent version of this document can be viewed at the PostgreSQL web site, http://www.PostgreSQL.org. @@ -253,14 +253,18 @@ Indexes * Allow the creation of bitmap indexes which can be quickly combined with other bitmap indexes - Bitmap indexes index single columns and can be combined with other bitmap + 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. + 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. * Allow non-bitmap indexes to be combined - Do loUse bitmaps to combine non-bitmap indexes + Do lookups on non-bitmap indexes and create bitmaps in memory that can be + combined with other indexes. + * Allow use of indexes to search for NULLs One solution is to create a partial index on an IS NULL expression.