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.dolw...@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 >
