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https://issues.apache.org/jira/browse/DRILL-1328?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15290068#comment-15290068
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ASF GitHub Bot commented on DRILL-1328:
---------------------------------------

Github user sudheeshkatkam commented on a diff in the pull request:

    https://github.com/apache/drill/pull/425#discussion_r63799874
  
    --- Diff: 
exec/java-exec/src/main/java/org/apache/drill/exec/store/dfs/FormatPlugin.java 
---
    @@ -48,7 +48,7 @@
     
       public FormatMatcher getMatcher();
     
    -  public AbstractWriter getWriter(PhysicalOperator child, String location, 
List<String> partitionColumns) throws IOException;
    +  public AbstractWriter getWriter(PhysicalOperator child, String location, 
boolean append, List<String> partitionColumns) throws IOException;
    --- End diff --
    
    Could pass a map of options, when "append" is an option?


> Support table statistics
> ------------------------
>
>                 Key: DRILL-1328
>                 URL: https://issues.apache.org/jira/browse/DRILL-1328
>             Project: Apache Drill
>          Issue Type: Improvement
>            Reporter: Cliff Buchanan
>             Fix For: Future
>
>         Attachments: 0001-PRE-Set-value-count-in-splitAndTransfer.patch
>
>
> This consists of several subtasks
> * implement operators to generate statistics
> * add "analyze table" support to parser/planner
> * create a metadata provider to allow statistics to be used by optiq in 
> planning optimization
> * implement statistics functions
> Right now, the bulk of this functionality is implemented, but it hasn't been 
> rigorously tested and needs to have some definite answers for some of the 
> parts "around the edges" (how analyze table figures out where the table 
> statistics are located, how a table "append" should work in a read only file 
> system)
> Also, here are a few known caveats:
> * table statistics are collected by creating a sql query based on the string 
> path of the table. This should probably be done with a Table reference.
> * Case sensitivity for column statistics is probably iffy
> * Math for combining two column NDVs into a joint NDV should be checked.
> * Schema changes aren't really being considered yet.
> * adding getDrillTable is probably unnecessary; it might be better to do 
> getTable().unwrap(DrillTable.class)



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