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- INSERT OVERWRITE statements to directories, local directories, and tables (or partitions) can all be used together within the same query.
- INSERT OVERWRITE statements to HDFS filesystem directories are the best way to extract large amounts of data from Hive. Hive can write to HDFS directories in parallel from within a map-reduce job.
- The directory is, as you would expect, OVERWRITten; in other words, if the specified path exists, it is clobbered and replaced with the output.
- As of Hive 0.11.0 the separator used can be specified, in earlier versions it was always the ^A character (\001)