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https://issues.apache.org/jira/browse/DRILL-4905?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15573626#comment-15573626
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ASF GitHub Bot commented on DRILL-4905:
---------------------------------------

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

    https://github.com/apache/drill/pull/597#discussion_r83335982
  
    --- Diff: 
exec/java-exec/src/test/java/org/apache/drill/exec/store/parquet/TestParquetGroupScan.java
 ---
    @@ -117,4 +119,18 @@ public void testSelectEmptyNoCache() throws Exception {
             uex.getMessage()), uex.getMessage().contains(expectedMsg));
         }
       }
    +
    +  @Test
    +  public void testLimit() throws Exception {
    +    List<QueryDataBatch> results = 
testSqlWithResults(String.format("select * from cp.`parquet/limitTest.parquet` 
limit 1"));
    --- End diff --
    
    Also, can you add a unit test with LIMINT n , where n > # of rows in the 
table? 


> Push down the LIMIT to the parquet reader scan to limit the numbers of 
> records read
> -----------------------------------------------------------------------------------
>
>                 Key: DRILL-4905
>                 URL: https://issues.apache.org/jira/browse/DRILL-4905
>             Project: Apache Drill
>          Issue Type: Bug
>          Components: Storage - Parquet
>    Affects Versions: 1.8.0
>            Reporter: Padma Penumarthy
>            Assignee: Padma Penumarthy
>             Fix For: 1.9.0
>
>
> Limit the number of records read from disk by pushing down the limit to 
> parquet reader.
> For queries like
> select * from <table> limit N; 
> where N < size of Parquet row group, we are reading 32K/64k rows or entire 
> row group. This needs to be optimized to read only N rows.
>  



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