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Hive >> mail # user >> Fwd: Map join optimization issue


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Fwd: Map join optimization issue
Hello all,
I am trying to join two tables, the smaller being of size 4GB. When I set
hive.mapjoin.smalltable.filesize parameter above 500MB, Hive tries to
perform a local task to read the smaller file. This of-course fails since
the file size is greater and the backup common join is then run. What I do
not understand is why did Hive attempt a map join when small file size was
greater than the smalltable.filesize parameter.
~Mayuresh