[GitHub] [arrow-datafusion] alamb opened a new pull request #256: Implement count distinct for dictionary arrays

[GitBox <gi...@apache.org>]

alamb opened a new pull request #256:
URL: https://github.com/apache/arrow-datafusion/pull/256


   # Which issue does this PR close?
   
   Closes https://github.com/apache/arrow-datafusion/issues/249
   
   # Rationale for this change
   I have dictionary encoded data that I want to be able to compute distinct counts
   
   # What changes are included in this PR?
   This implementation has the the basic "get it working" version. A more optimized implementation (e.g. only looking at the dictionary contents) is left for a subsequent PR and I will file another ticket to track better the performance
   
   # Are there any user-facing changes?
   queries like `select count(distinct tag_col) from ...` are now supported when `tag_col` is a dictionary encoded column
   


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[GitHub] [arrow-datafusion] alamb merged pull request #256: Implement count distinct for dictionary arrays

[GitBox <gi...@apache.org>]

alamb merged pull request #256:
URL: https://github.com/apache/arrow-datafusion/pull/256


   


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