EVL – ETL Tool

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Table of Contents


(since EVL 2.4)

Read <file.json> or standard input, guess data types, and write EVD to standard output or to <file.evd>.


  [<file.json>] [-o|--output=<file.evd>]

  ( --help | --usage | --version )


-d, --date=<format>

by default it tries only ‘%Y-%m-%d’, then ‘%Y%m%d’, then ‘%d.%m.%Y

-l, --null=<string>

to specify what string is used for NULL values in JSON, empty string is allowed

-o, --output=<file.evd>

write output into file <file.evd> instead of standard output

-q, --quote=<char>

do not guess if fields are quoted, but suppose <char> as quotation character

-s, --separator=<char>

do not guess the separator, but use <char> instead

-t, --datetime=<format>

by default it tries only ‘%Y-%m-%d %H:%M:%S’, then ‘%Y%m%d%H%M%S

-v, --verbose

print to STDERR info/debug messages


print this help and exit


print short usage information and exit


print version and exit


  1. Having some.json:

    This command:

    json2evd --null="" some.json

    will produce:

    id       int              null="" sep=";"
    started  date("%Y-%m-%d") null="" sep=";"
    value    string           null="" sep="\n"