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https://issues.apache.org/jira/browse/SPARK-8380?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14588196#comment-14588196
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Shivaram Venkataraman commented on SPARK-8380:
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Thanks for the update. I'm going to mark this issue as resolved. BTW if there 
are documentation changes that you think will be helpful feel free to create 
JIRAs / PRs for them

> SparkR mis-counts
> -----------------
>
>                 Key: SPARK-8380
>                 URL: https://issues.apache.org/jira/browse/SPARK-8380
>             Project: Spark
>          Issue Type: Bug
>          Components: SparkR
>    Affects Versions: 1.4.0
>            Reporter: Rick Moritz
>
> On my dataset of ~9 Million rows x 30 columns, queried via Hive, I can 
> perform count operations on the entirety of the dataset and get the correct 
> value, as double checked against the same code in scala.
> When I start to add conditions or even do a simple partial ascending 
> histogram, I get discrepancies.
> In particular, there are missing values in SparkR, and massively so:
> A top 6 count of a certain feature in my dataset results in an order of 
> magnitude smaller numbers, than I get via scala.
> The following logic, which I consider equivalent is the basis for this report:
> counts<-summarize(groupBy(df, df$col_name), count = n(tdf$col_name))
> head(arrange(counts, desc(counts$count)))
> versus:
> val table = sql("SELECT col_name, count(col_name) as value from df  group by 
> col_name order by value desc")
> The first, in particular, is taken directly from the SparkR programming 
> guide. Since summarize isn't documented from what I can see, I'd hope it does 
> what the programming guide indicates. In that case this would be a pretty 
> serious logic bug (no errors are thrown). Otherwise, there's the possibility 
> of a lack of documentation and badly worded example in the guide being behind 
> my misperception of SparkRs functionality.



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