Re: suggestion: set default statistics to 100 for numerics - Mailing list pgsql-hackers

From Alvaro Herrera
Subject Re: suggestion: set default statistics to 100 for numerics
Date
Msg-id 20040701223753.GC13816@dcc.uchile.cl
Whole thread Raw
In response to suggestion: set default statistics to 100 for numerics  (Joseph Shraibman <jks@selectacast.net>)
Responses Re: suggestion: set default statistics to 100 for numerics  (Joseph Shraibman <jks@selectacast.net>)
List pgsql-hackers
On Wed, Jun 30, 2004 at 10:56:53PM -0400, Joseph Shraibman wrote:
> Seeing how small storage for a number type is compared to a text type, 
> and seeing how they tend to be queried on a lot, shouldn't it be 
> reasonable for the default stats number for numerics to be 100 instead 
> of 10?

The problem is not only storage space, but also the optimizer runtime;
which would have to munge the larger amount of data ... not sure if this
is critical but enlarging it by default for all numeric columns may not
be desirable.

Anyway ISTM a better rule would be enlarging the default stats number
for columns that are part of an index, rather than using the datatype.

-- 
Alvaro Herrera (<alvherre[a]dcc.uchile.cl>)
"Porque Kim no hacia nada, pero, eso sí,
con extraordinario éxito" ("Kim", Kipling)



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