[jira] [Created] (DRILL-8083) HttpdLogBatchReader creates unnecessary empty maps

["Paul Rogers (Jira)" <ji...@apache.org>]

Paul Rogers created DRILL-8083:
----------------------------------

             Summary: HttpdLogBatchReader creates unnecessary empty maps
                 Key: DRILL-8083
                 URL: https://issues.apache.org/jira/browse/DRILL-8083
             Project: Apache Drill
          Issue Type: Bug
    Affects Versions: 1.19.0
            Reporter: Paul Rogers


Run the {{TestHTTPDLogReader.testStarRowSet}} test. Set a breakpoint in
{{MapWriter.SingleMapWriter.endWrite}}. Step into the {{super.endWrite()}}
method which will walk the set of child fields. Notice that there are none
for any of the several map fields.

One can see that empty maps are expected in the
{{TestHTTPDLogReader.expectedAllFieldsSchema()}} method.

Maps (i.e. tuples) are not well defined in SQL. Although Drill makes great
efforts to support them, an empty tuple is not well defined even in Drill:
there is nothing one can do with such fields.

Suggestion: don't create a map field if there are to be no members of the
map.

Affected maps:

* {{request_firstline_original_uri_query_$}}
* {{request_firstline_uri_query_$}}
* {{request_referer_last_query_$}}
* {{request_referer_query_$}}



--
This message was sent by Atlassian Jira
(v8.20.1#820001)