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# hdfs.parts

Returns the number of parts composing a file in HDFS.

Usage

    hdfs.parts(
            dfs.id)

Arguments

dfs.id

  The name of a file in HDFS. The file name can include a path that is either absolute or relative to the current path.

Usage Notes

HDFS splits large files into parts, which provide a basis for the parallelization of MapReduce jobs. The more parts an HDFS file has, the more mappers can run in parallel.

Return Value

The number of parts composing the object, or `0` if the object does not exist in HDFS

Example

This example shows that the ontime_R file in HDFS has one part:

    R> hdfs.parts("ontime_R")
    [1] 1