hadoop - Example about how set a Hive property from within a Hive query -


i need quick example of how change property in hive using query, instance, change property 'mapred.reduce.tasks' so, how perform change within query.

i'm training self hdpcd exam , 1 of goals in exam 'set hadoop or hive configuration property within hive query' suppose it's not same performing in hive console like:

set mapred.reduce.tasks=2;

to change hadoop , hive configuration variable need use set in hive query. change made applicable query session

set -v prints hadoop , hive configuration variables.

set mapred.reduce.tasks=xx // in hadoop 1.x set mapreduce.job.reduces=xx // in hadoop 2.x (yarn)

reset in query resets configuration default values


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