Re: How does Index Scan get used - Mailing list pgsql-sql

From Oliver Elphick
Subject Re: How does Index Scan get used
Date
Msg-id 1014425762.13241.2733.camel@linda
Whole thread Raw
In response to Re: How does Index Scan get used  (Tom Lane <tgl@sss.pgh.pa.us>)
List pgsql-sql
On Sat, 2002-02-23 at 00:11, Tom Lane wrote:
...
> Oh BTW: the "10 rows" Oliver was wondering about are not the number of
> rows the planner thinks are in the table; they're the estimated number
> of result rows.  Since there's no VACUUM ANALYZE stats available either,
> this is just a default selectivity estimate for the match clause (0.01)
> times the initial dummy reltuples value (1000).  Not much content in it
> at all, eh?

Thanks, Tom.  That was most informative.

-- 
Oliver Elphick                                Oliver.Elphick@lfix.co.uk
Isle of Wight                              http://www.lfix.co.uk/oliver
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    "The LORD bless thee, and keep thee; The LORD make his     face shine upon thee, and be gracious unto thee; The
LORD lift up his countenance upon thee, and give thee      peace."              Numbers 6:24-26 
 



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