Re: [PATCHES] Bitmapscan changes - Mailing list pgsql-hackers

From Heikki Linnakangas
Subject Re: [PATCHES] Bitmapscan changes
Date
Msg-id 46016B16.6080205@enterprisedb.com
Whole thread Raw
In response to Re: [PATCHES] Bitmapscan changes  ("Joshua D. Drake" <jd@commandprompt.com>)
Responses Re: [PATCHES] Bitmapscan changes  (Grzegorz Jaskiewicz <gj@pointblue.com.pl>)
List pgsql-hackers
Joshua D. Drake wrote:
> Right. My understanding is that the clustered index will gradually
> degrade to a normal btree, is that correct heikki?

That's right.

> We could of course resolve this by doing a reindex.

Not reindex, but cluster. How clustered the index can be depends on the 
clusteredness of the heap.

> The other item I think this would be great for is fairly static tables.
> Think about tables that are children of partitions that haven't been
> touched in 6 months. Why are we wasting space with them?

By touched, you mean updated, right? Yes, it's particularly suitable for 
static tables, since once you cluster them, they stay clustered. 
Log-tables that are only inserted to, in monotonically increasing key 
order, also stay clustered naturally.

--   Heikki Linnakangas  EnterpriseDB   http://www.enterprisedb.com


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