Re: Regarding Bitmap Scan

am  Tue, dem 17.10.2006, um 17:09:29 +0530 mailte soni de folgendes:
> I didn't understand the "Bitmap Scan" and the sentence "indexes will be
> dynamically converted to bitmaps in memory". What does mean by "Bitmap Scan" in
> database?

For instance, you have a large table with 5 indexes on this and a query
that checks conditions on this 5 columns.

PG is now able to combine this 5 indexes and performs only 1 bitmap
index scan on this table, and not 5 independet nested bitmap scans.

A realy very great performance-boost!


HTH, Andreas
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Andreas Kretschmer
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