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To: "Steve Atkins" <steve@blighty.com>,
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Subject: Re: index vs. seq scan choice?
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> Would it be possible to look at a much larger number of samples during  
> analyze,
> then look at the variation in those to generate a reasonable number of
> pg_statistic "samples" to represent our estimate of the actual  
> distribution?
> More datapoints for tables where the planner might benefit from it, fewer
> where it wouldn't.

	Maybe it would be possible to take note somewhere of the percentage of  
occurence of the most common value (in the OP's case, about 3%), in which  
case a quick decision can be taken to use the index without even looking  
at the value, if we know the most common one is below the index use  
threshold...