EVL – ETL Tool

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Table of Contents


(since EVL 2.0)

Write stdin or <f_in> into <parquet> directory as files of the size approximately of the size <file_size> MB. Compression can be turned on by –compression option.


is to be used in EVS job structure definition file. <f_in> is either input file or flow name.

evl writeparquet

is intended for standalone usage, i.e. to be invoked from command line and reading records from standard input.

EVD and EVS are EVL definition files, for details see evl-evd(5) and evl-evs(5).


  <f_in> <parquet> (<evd>|-d <inline_evd>) [-x|--text-input]
  [--size=<file_size>] [--impala]

evl writeparquet
  <parquet> (<evd>|-d <inline_evd>) [-x|--text-input]
  [--size=<file_size>] [--impala]

evl writeparquet
  ( --help | --usage | --version )


-d, --data-definition=<inline_evd>

either this option or the file <evd> must be presented. Example: -d ’id int, name string, started timestamp’


compression to be used, possible values are gzip, snappy, lz4, brotli, zstd, none. By default ’none’ is used, so no compression is applied


specify the number of MB, this size will be used for resulting files, default is 256 MB


produce a parquet file(s) to be used then by Apache Impala, i.e. store TIMESTAMP as INT96

-x, --text-input

suppose the input as text, not binary

Standard options:


print this help and exit


print short usage information and exit

-v, --verbose

print to stderr info/debug messages of the component


print version and exit