hadoop - What is the difference between partitioning and bucketing in hive? -


this question has answer here:

i not clear difference between partitioning , bucketing in hive , appreciate if can provide details example.

here nice difference between buckets , partitioning.

basically both partitioning , bucketing slice data executing query more efficiently on non-sliced data. major difference number of slices keep on changing in case of partitioning data modified, bucketing number of slices fixed specified while creating table.

bucketing happen using hash algorithm , modulo on number of buckets. so, row might inserted of bucket. bucketing can used sampling of data, joining 2 data sets more , more.


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