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This is the support for Probabilistic Mass Function (PMF) from Apache DataSketches KLL algorithm collection. It receives a serialized KLL sketch and one or more float values to represent ranges in the sketched values. E.g. [1, 5, 10] will mean the following ranges: (-inf, 1), [1, 5), [5, 10), [10, +inf) Returns a comma separated string where each value in the string is a number in the range of [0,1] and shows that what percentage of the data is in the particular ranges. Note, ds_kll_pmf() should return an Array of doubles as the result but with that we have to wait for the complex type support. Until, we provide ds_kll_pmf_as_string() that can be deprecated once we have array support. Tracking Jira for returning complex types from functions is IMPALA-9520. Example: select ds_kll_pmf_as_string(ds_kll_sketch(float_col), 2, 4, 10) from alltypes; +----------------------------------------------------------+ | ds_kll_pmf_as_string(ds_kll_sketch(float_col), 2, 4, 10) | +----------------------------------------------------------+ | 0.202192,0.199452,0.598356,0 | +----------------------------------------------------------+ Change-Id: I222402f2dce2f49ab2b3f6e81a709da5539293ba Reviewed-on: http://gerrit.cloudera.org:8080/16336 Reviewed-by: Gabor Kaszab <gaborkaszab@cloudera.com> Tested-by: Impala Public Jenkins <impala-public-jenkins@cloudera.com>