So this presents the fact that pg_stattuple should prevent and guess [taking a sample?] that a table needs an urgent lookup instead of ending the scan and presenting real numbers?
g.-
On 2/13/06, Chris Browne <cbbrowne@acm.org> wrote:gbarosio@gmail.com (Guido Barosio) writes:
> quote: " If you are quite sure it has few if any dead tuples, it might be
> something to try to avoid VACUUMing except as needed to evade the 2^31
> transaction limit..."
> You may use the pg_stattuple software, included in the /contrib . This will show you the current scenery, and whether you shall clean or not dead tuples.
The trouble with pg_stattuple() is that running it is virtually as
expensive as running the vacuum. For a bit table, you pay all the I/O
cost, and any costs of the super-long-running-transaction and don't
even get any cleanup for that cost.
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