[GitHub] [spark] viirya opened a new pull request #24482: [SPARK-27581][SQL] DataFrame countDistinct("*") shouldn't fail with AnalysisException

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

viirya opened a new pull request #24482: [SPARK-27581][SQL] DataFrame countDistinct("*") shouldn't fail with AnalysisException
URL: https://github.com/apache/spark/pull/24482
 
 
   ## What changes were proposed in this pull request?
   
   Currently `countDistinct("*")` doesn't work. An analysis exception is thrown:
   
   ```scala
   val df = sql("select id % 100 from range(100000)")
   df.select(countDistinct("*")).first()
   
   org.apache.spark.sql.AnalysisException: Invalid usage of '*' in expression 'count';
   ```
   
   Users need to use `expr`.
   
   ```scala
   df.select(expr("count(distinct(*))")).first()
   ```
   
   This limits some API usage like `df.select(count("*"), countDistinct("*))`.
   
   The PR takes the simplest fix that lets analyzer expand star and resolve `count` function.
   
   ## How was this patch tested?
   
   Added unit test.

----------------------------------------------------------------
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.
 
For queries about this service, please contact Infrastructure at:
users@infra.apache.org


With regards,
Apache Git Services

---------------------------------------------------------------------
To unsubscribe, e-mail: reviews-unsubscribe@spark.apache.org
For additional commands, e-mail: reviews-help@spark.apache.org