How to calculate median in AWS Redshift?

amazon-redshift

Solution

And as of 2014-10-17, Redshift supports the MEDIAN window function:

# select min(median) from (select median(num) over () from temp);
 min 
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 4.0

Problem

Most databases have a built in function for calculating the median but I don't see anything for median in Amazon Redshift. You could calculate the median using a combination of the nth_value() and count() analytic functions but that seems janky. I would be very surprised if an analytics db didn't have a built in method for computing median so I'm assuming I'm missing something. http://docs.aws.amazon.com/redshift/latest/dg/r_Examples_of_NTH_WF.html http://docs.aws.amazon.com/redshift/latest/dg/c_Window_functions.html

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