Hi, Min,

I am somewhat unsure of what operations you are referring to by 
"high-cardinality table join."  The following is a quick description 
of the binning strategy.  Please clarify your question and I will give 
it another try to answer it..

John

----------------------
One can explicitly tell FastBit to bin any numerical values by using 
an indexing specification containing a <binninb .../> directive. 
However, if you neglect to specify an explicit directive, here is what 
happens.

- for integer values, if the difference between the min and max is 
less than 1000 or less than 10% of the number of rows, then each 
distinct value will get its own bin (i.e., no binning).  Otherwise, a 
default binning strategy is used.

- for floating-point values, the default binning strategy is used

- the default binning strategy samples the current values, build an 
exact histogram on the sampled values, divide the histogram into a 
certain number of bins, typically around 10,000 bins.  We call this 
approximate equal-weight bins.



On 3/19/2010 3:57 AM, Min Zhou wrote:
> Hi all,
> Can anyone give me a description on the implementation fastbit deal
> with high-cardinality table join?
> Does it use binning? How do they join?
>
>
> Thanks,
> Min
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