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From Adam Kawa <kawa.a...@gmail.com>
Subject Re: hive.query.string not reflecting the current query
Date Tue, 03 Dec 2013 18:33:19 GMT
Hmmm?

Maybe it is related to the fact, that a query:
> select * from mytable limit 100;
does not start any MapReduce job. It is starts a reading operation from
HDFS (and a communication with MetaStore to know what is the schema and how
to parse the data using InputFormat and SerDe).

For example, If you run a query that has the same functionality (i.e. to
show all content of the table by specifying all columns in SELECT)
> select column1, column2, ... columnN from mytable limit 100;
then a map-only job will be started and maybe (?) hive.query.string will
contain this query..


2013/12/3 Petter von Dolwitz (Hem) <petter.von.dolwitz@gmail.com>

> Hi,
>
> I use hive 0.11 with a five machine cluster. I am reading the property
> hive.query.string from a custom RecordReader (used for reading external
> tables).
>
> If I first invoke a query like
>
> select * from mytable where mycolumn='myvalue';
>
> I get the correct query string in this property.
>
> If I then invoke
>
> select * from mytable limit 100;
>
> the property hive.query.string still contains the first query. Seems like
> hive uses local mode for the second query. Don't know if it is related.
>
> Anybody knows why the query string is not updated in the second case?
>
> Thanks,
> Petter
>

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